Home » Public Forums » GMCnet » [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices.
| [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332066] |
Mon, 14 May 2018 13:29  |
BobDunahugh
Messages: 2465
Registered: October 2010
Location: Cedar Rapids, IA
Karma: 11
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We've had a GMC since 2003. Go to all the GMCMI events now. No mater were they are. Totally rebuilt 3 - 78 Royales. Two for us. One for a close friend. Now building another GMC to sell . In all this building. It's been very clear to me that GMC did a great job in engineering these coaches to high engineering standards, and the technology of the day. In changing anything. You need to evaluate if this new produce changing the original engineering parameters.
With our GMC's in the 40 to 45 years old range. We have lots of new products to install. Some products enhance the original GM designs. Mostly because of new technology that wasn't available, or known in the 70's. Electronic Fuel Injection ( EFI ) is a prime example. And our modern fuels are now formulated to be atomized by way of the pressures that EFI provides. We have EFI/computer, spark control systems in the Howell EFI package. I'm looking forward to the day when we can remove the camshaft from our engines. And have the valves controlled electronically. This will be a terrific enhancement in the way of better valve timing. Mileage, and torque. We now have an electronically controlled fan clutch to help stabilize our engine temps more closely. This is done by sensing engine temps. Not air temps from the radiator. Engine electric water pumps can't be far away. We're removing the failure prone tank selector switch in exchange for a two pump fuel delivery system. We have our original front wheel bearings now that will never have to be remove to get new grease put in them. Thus a true lifetime bearing now. We have some new air bags Due to the original bags not being produced. We have the Quad bag system that has some pros/cons ( Pros. Is a little more stable on the road. Can maintain ride height if a bag fails. Cons. Doesn't handle speed bumps as well. ) And maintains the original rear suspension design. Rear disc brakes to enhance braking. The original rear drum brakes did a good job. But you had to adjust them each year. Jim K at Applied came up with the 3:70 final drive. Fantastic improvement. This list is too long to continue.
Next are two ideas that don't fallow SAE ( Society of Automotive Engineers ) practices.
1 All wheels are made with what's called. Offset. This offset is to place the center of the tire in a very particular position over the Inter/outer wheel bearings. This position is in reference to the load carrying capacity of each of the inter/outer wheel bearings. Our rims have a lot of offset. This can be seen in comparing standard pickup rims to ours. Our lug nuts are out at the tire side wall. Pickup lug nuts are closer to being between the sidewalls. Most cars, and trucks don't have the front and rear tires travel in the same track. Our GMC's have the rear tires tracking wider then the front. There are spacers on the market that will space the front tires out to match the rear tire track. These spacers put excessive loads on the outer front wheel bearings. Pot holes/rough road surfaces acerbate this issue greatly. I would never ever install these on any GMC.
2 An SAE standard has stated for decades that upper/lower A frames should be parallel to each other for proper suspension geometry. With the 1 ton kit. The A frames are no longer parallel to each other. It's said that the 1 ton has a lifetime bearing. The lifetime is over when the bearing fails. Not the life of your GMC, or YOU. SORRY. We have lifetime bearings now that we can lube. And comply to SAE standards. Most original bearing have gone well over 100,000 miles over 40 some years before ever being serviced. From what I've been told. The GM 1 ton bearings are larger. This maybe true. But this 1 ton kit also has the spacer that's listed above. ( I believe the 1 ton spacer is even longer. ) GM never intended for the 1 ton bearing to be loaded in this over loaded condition all the time. ( As a note.) We just talked about overloading the rear tires/ bearings by running 3 tires with the Quad bag. At least the rear wheel bearing weren't being run with the bearings improperly loaded. I put a 1 ton unit in a friends GMC. Now wish that I wouldn't have done it. I know of many owners that have installed the 1 ton. Talk about the improved handling. But most of those GMC's were riding on worn out parts. Dave Lenzi IS the true expert on brakes/suspension components for GMC's. There is no debate on his knowledge. At the next GMCMI event. Ask Dave for a short version of his opinion of the 1 ton. I'm not saying. Don't install the 1 ton. I'm just saying that this is some info on it. It's your GMC. I'll personally go with SAE approved design applications.
GM did a lot of R/D in make our GMC's. We need to keep their design reasoning in mine. Items like electronic fuel injection WITH spark control. That is a technology that wasn't available back then. It's an excellent upgrade that should be at the top of every GMC owners list. I was slow to get mine on. Love it. My 2 cent on the topic. Bob Dunahugh
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332078 is a reply to message #332066] |
Tue, 15 May 2018 07:39  |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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Your comment on the one ton front end reminds me of stereo freaks who spent beaucoup dollars on connecting cables. When they say it sounds much better, they're reporting the truth. Not because the cables were any better than what you get from MonoPrice though. Because they removed a piece of #24 wire to the speaker and replaced it with #10 or #6 conductors which can handle the current. Or replaced the frayed cheeep input cables with one with proper shields. "Oxygen - Free" and "Minimum Skin Effect" are basically bullshit in this application. The IEEE tested these double blind, the results were as I note. Also, there's 'placebo effect' which essentially says "I paid money therefore it's better".
Now this doesn't say the one - ton or the four-bag is or isn't a Good Thing. What I'd like to see is a pair of coaches with normal (100K plus) mileage on them on a skid pad. Then put the one ton on one of them, and renew all the same parts in the other but leave it stock (All bushings, bearings, etc.) Then test them again. The same with air bag systems. The results might well convince us to make the mod or mods. Alls we have right now is subjective experience.
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332086 is a reply to message #332078] |
Tue, 15 May 2018 09:01 |
Keith V
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
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The good things about the 1 ton is the heavy duty replaceable bearing and the larger brakes.
The bad thing is the suspension geometry.
I was sorry I rebuilt the original until I talked to Dave Lenzi, Now I'm glad I stayed with the stock system, handling is important to me. The stock system is OK, not great, definitely don't want to make it worse!
________________________________
From: Gmclist on behalf of Johnny Bridges via Gmclist
Sent: Tuesday, May 15, 2018 7:39 AM
To: gmclist@list.gmcnet.org
Cc: Johnny Bridges
Subject: Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices.
Your comment on the one ton front end reminds me of stereo freaks who spent beaucoup dollars on connecting cables. When they say it sounds much
better, they're reporting the truth. Not because the cables were any better than what you get from MonoPrice though. Because they removed a piece of
#24 wire to the speaker and replaced it with #10 or #6 conductors which can handle the current. Or replaced the frayed cheeep input cables with one
with proper shields. "Oxygen - Free" and "Minimum Skin Effect" are basically bullshit in this application. The IEEE tested these double blind, the
results were as I note. Also, there's 'placebo effect' which essentially says "I paid money therefore it's better".
Now this doesn't say the one - ton or the four-bag is or isn't a Good Thing. What I'd like to see is a pair of coaches with normal (100K plus)
mileage on them on a skid pad. Then put the one ton on one of them, and renew all the same parts in the other but leave it stock (All bushings,
bearings, etc.) Then test them again. The same with air bag systems. The results might well convince us to make the mod or mods. Alls we have right
now is subjective experience.
--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
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Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332093 is a reply to message #332078] |
Tue, 15 May 2018 10:35 |
Richard Denney
Messages: 920
Registered: April 2010
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It’s true that most people are replacing worn-out stuff.
But I don’t see that many people extolling the virtues of handling on the
one-ton, as much as extolling the virtues of strength and maintainability.
And brakes.
Putting a zerk into the stock hub doesn’t address all its issues. The stock
design relies on a face seal and a shaft seal, and the bearing fit has to
be perfect for the face seal to snug up to the stub axle just the right
amount. It also relies on a spacer to determine bearing adjustment, which
puts a lot of manufacturing stress on the machining of the knuckle and hub.
Dave is absolutely up to that standard and beyond it. But he will retire
someday. The one-ton kits have to be done right, of course, but it’s not
quite as demanding.
The lower arms are known to suffer from fatigue cracking, particularly the
73’s. That’s about a kilobuck, plus a $300 core charge that is
nonrefundable with ‘73 arms. Those come with new ball joints and bushings.
Add another hundred bucks for the ball joint and pushing for the upper.
Just dealing with the A-arms costs as much the one-ton kit Manny sold, and
then there’s the cost of remanufactured knuckles and new front bearings.
Not to mention the declining availability of quality replacements.
I was driving with a spun starboard outer bearing and a broken port-side
lower ball joint, and didn’t know it. I found out just because I was
replacing a CV joint boot. Inspection is difficult with the stock system,
and inspection disassembly imposes risk and wear in its own right.
Trucks that natively used the one-ton parts used front wheels with lots of
offset for one reason: so that they have the same wheels as used in the
dually rear axle and thus only need one spare. Those trucks use a spacer
from the factory so that the dually wheel will clear the brakes, so spacer
use is baked into the bearing specification.
So, why did GM use dually wheels? So they could move the rear suspension
outboard, and so they move the front wheel rotation around the center of
the bearing. Using a wheel with less offset is routine, and has the same
effect as using a spacer. We end up with six of the same kind of wheel.
It’s true that the a-arms are not parallel. The handling effect of that is
theoretical at best. It means camber will increase (slightly) with jounce,
and for the life of me I can’t figure why that’s bad for the average
driver. Nearly everyone who has installed one has reported only
improvement, and even though the improvement may be due to replacing
worn-out stuff, it tells me that most are not noticing a disimprovement.
But it’s also true that the brakes on the one-ton are significantly bigger
than the brakes on the original, which were sized for a car back when the
state of the practice had barely begun using front disks (my 1970 Cutlass
had drums all around, and my ‘74 GMC Pickup had front disks). That’s what I
noticed immediately, and my previous brakes were at factory spec.
Putting a good front end on a coach is expensive, and the one-ton kit
actually turns out not to be the most expensive alternative. Plus, we can
just buy bearings—we don’t have to worry about having only Timken bearings,
or grinding grooves in (the correct!) spacer, or drilling for zerks. And we
get big brakes.
I have worked with the automakers for years in one of several capacities.
Some things they design very well. Their cost engineering is the best in
the manufacturing world. But they are also expected, especially on
specialty vehicles, to use parts and assemblies already being manufactured,
even when doing so is a compromise. The one-ton kit is a different
compromise, but the original was still a compromise.
It’s the same with the rear. I’ve heard it argued that the compliance of
the forward bogie is important for tight turns at slow speeds. But that
does not outweigh the effect of the forward trail at highway speeds. The
forces will always be trying to push the front bogie to one side. But the
design made manufacturing easy—the rear suspension was complete as an
assembly and could be installed as a unit. A tracking device on the front
prevents that wandering, and the reaction rod keeps the coach from trying
to climb over the forward bogie in hard braking. Both are substantial
improvements on the original design.
These are not “Monster Cable” improvements.
Rick “thinking hard about sustainability” Denney
On Tue, May 15, 2018 at 9:03 AM Johnny Bridges via Gmclist <
gmclist@list.gmcnet.org> wrote:
> Your comment on the one ton front end reminds me of stereo freaks who
> spent beaucoup dollars on connecting cables. When they say it sounds much
> better, they're reporting the truth. Not because the cables were any
> better than what you get from MonoPrice though. Because they removed a
> piece of
> #24 wire to the speaker and replaced it with #10 or #6 conductors which
> can handle the current. Or replaced the frayed cheeep input cables with one
> with proper shields. "Oxygen - Free" and "Minimum Skin Effect" are
> basically bullshit in this application. The IEEE tested these double
> blind, the
> results were as I note. Also, there's 'placebo effect' which essentially
> says "I paid money therefore it's better".
>
> Now this doesn't say the one - ton or the four-bag is or isn't a Good
> Thing. What I'd like to see is a pair of coaches with normal (100K plus)
> mileage on them on a skid pad. Then put the one ton on one of them, and
> renew all the same parts in the other but leave it stock (All bushings,
> bearings, etc.) Then test them again. The same with air bag systems. The
> results might well convince us to make the mod or mods. Alls we have right
> now is subjective experience.
>
> --johnny
> --
> 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> "I forgive them all, save those who hurt the dogs. They must answer to me
> in hell" - ol Andy, paraphrased
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Rick Denney
73 x-Glacier 230 "Jaws"
Off-list email to rick at rickdenney dot com
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332097 is a reply to message #332093] |
Tue, 15 May 2018 11:13 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
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Senior Member |
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I agree with Rick 100%. Of all the things I've done to the '76 X-BIrchaven
over the past 20 years, which includes 'most everything I've heard of, the
ranking would go something like this:
1. "True-tracks" eliminate the "One-handled wheelbarrow" effect of
the OEM leading arms.
2. Reaction arms eliminated the "Pole vaulting" effect of the OEM
leading arms (True-tracks are an
option with Manny's arms and some of Applied's.
3. 1-Ton front end -- what Rick said
Ken H.
On Tue, May 15, 2018 at 11:36 AM Richard Denney wrote:
> It’s true that most people are replacing worn-out stuff.
>
> But I don’t see that many people extolling the virtues of handling on the
> one-ton, as much as extolling the virtues of strength and maintainability.
> And brakes.
>
> Putting a zerk into the stock hub doesn’t address all its issues. The stock
> design relies on a face seal and a shaft seal, and the bearing fit has to
> be perfect for the face seal to snug up to the stub axle just the right
> amount. It also relies on a spacer to determine bearing adjustment, which
> puts a lot of manufacturing stress on the machining of the knuckle and hub.
> Dave is absolutely up to that standard and beyond it. But he will retire
> someday. The one-ton kits have to be done right, of course, but it’s not
> quite as demanding.
>
> The lower arms are known to suffer from fatigue cracking, particularly the
> 73’s. That’s about a kilobuck, plus a $300 core charge that is
> nonrefundable with ‘73 arms. Those come with new ball joints and bushings.
> Add another hundred bucks for the ball joint and pushing for the upper.
>
> Just dealing with the A-arms costs as much the one-ton kit Manny sold, and
> then there’s the cost of remanufactured knuckles and new front bearings.
> Not to mention the declining availability of quality replacements.
>
> I was driving with a spun starboard outer bearing and a broken port-side
> lower ball joint, and didn’t know it. I found out just because I was
> replacing a CV joint boot. Inspection is difficult with the stock system,
> and inspection disassembly imposes risk and wear in its own right.
>
> Trucks that natively used the one-ton parts used front wheels with lots of
> offset for one reason: so that they have the same wheels as used in the
> dually rear axle and thus only need one spare. Those trucks use a spacer
> from the factory so that the dually wheel will clear the brakes, so spacer
> use is baked into the bearing specification.
>
> So, why did GM use dually wheels? So they could move the rear suspension
> outboard, and so they move the front wheel rotation around the center of
> the bearing. Using a wheel with less offset is routine, and has the same
> effect as using a spacer. We end up with six of the same kind of wheel.
>
> It’s true that the a-arms are not parallel. The handling effect of that is
> theoretical at best. It means camber will increase (slightly) with jounce,
> and for the life of me I can’t figure why that’s bad for the average
> driver. Nearly everyone who has installed one has reported only
> improvement, and even though the improvement may be due to replacing
> worn-out stuff, it tells me that most are not noticing a disimprovement.
>
> But it’s also true that the brakes on the one-ton are significantly bigger
> than the brakes on the original, which were sized for a car back when the
> state of the practice had barely begun using front disks (my 1970 Cutlass
> had drums all around, and my ‘74 GMC Pickup had front disks). That’s what I
> noticed immediately, and my previous brakes were at factory spec.
>
> Putting a good front end on a coach is expensive, and the one-ton kit
> actually turns out not to be the most expensive alternative. Plus, we can
> just buy bearings—we don’t have to worry about having only Timken bearings,
> or grinding grooves in (the correct!) spacer, or drilling for zerks. And we
> get big brakes.
>
> I have worked with the automakers for years in one of several capacities.
> Some things they design very well. Their cost engineering is the best in
> the manufacturing world. But they are also expected, especially on
> specialty vehicles, to use parts and assemblies already being manufactured,
> even when doing so is a compromise. The one-ton kit is a different
> compromise, but the original was still a compromise.
>
> It’s the same with the rear. I’ve heard it argued that the compliance of
> the forward bogie is important for tight turns at slow speeds. But that
> does not outweigh the effect of the forward trail at highway speeds. The
> forces will always be trying to push the front bogie to one side. But the
> design made manufacturing easy—the rear suspension was complete as an
> assembly and could be installed as a unit. A tracking device on the front
> prevents that wandering, and the reaction rod keeps the coach from trying
> to climb over the forward bogie in hard braking. Both are substantial
> improvements on the original design.
>
> These are not “Monster Cable” improvements.
>
> Rick “thinking hard about sustainability” Denney
>
>
> On Tue, May 15, 2018 at 9:03 AM Johnny Bridges via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> Your comment on the one ton front end reminds me of stereo freaks who
>> spent beaucoup dollars on connecting cables. When they say it sounds
> much
>> better, they're reporting the truth. Not because the cables were any
>> better than what you get from MonoPrice though. Because they removed a
>> piece of
>> #24 wire to the speaker and replaced it with #10 or #6 conductors which
>> can handle the current. Or replaced the frayed cheeep input cables with
> one
>> with proper shields. "Oxygen - Free" and "Minimum Skin Effect" are
>> basically bullshit in this application. The IEEE tested these double
>> blind, the
>> results were as I note. Also, there's 'placebo effect' which essentially
>> says "I paid money therefore it's better".
>>
>> Now this doesn't say the one - ton or the four-bag is or isn't a Good
>> Thing. What I'd like to see is a pair of coaches with normal (100K plus)
>> mileage on them on a skid pad. Then put the one ton on one of them, and
>> renew all the same parts in the other but leave it stock (All bushings,
>> bearings, etc.) Then test them again. The same with air bag systems.
> The
>> results might well convince us to make the mod or mods. Alls we have
> right
>> now is subjective experience.
>>
>> --johnny
>> --
>> 76 26' Eleganza(?) with beaucoup mods and add - ons.
>> Braselton, Ga.
>> "I forgive them all, save those who hurt the dogs. They must answer to
> me
>> in hell" - ol Andy, paraphrased
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> --
> Rick Denney
> 73 x-Glacier 230 "Jaws"
> Off-list email to rick at rickdenney dot com
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332100 is a reply to message #332066] |
Tue, 15 May 2018 11:30 |
BobDunahugh
Messages: 2465
Registered: October 2010
Location: Cedar Rapids, IA
Karma: 11
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Senior Member |
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A few years ago. I did a driving comparison at a road race track event. We had 2- 78 GMC's there. One original. The other had the 1 Ton. I had 6 drivers take each GMC on a 12 mile drive. ( No interstate ) Remember. For these guys. Handling is everything. Not just that they can keep it between the lines. Just told them to evaluate the handling of each. Told them nothing of the changes. All liked the handling of the original GMC the most. And were impressed on the handling of the original. Even being that big. 5 figured out on the drive about the A frames. 1 was getting close on that. 2 mentioned hints of torque steer. I'm not against the 1 Ton. But owners need to be aware of this side of the story. I'm with Dave Lenzi on this. I don't see an advantage. Well. EXCEPT. It's a cheep fix if everything up front needs to be replaced. Bob Dunahugh
________________________________
From: Bob Dunahugh
Sent: Monday, May 14, 2018 1:29 PM
To: gmclist@list.gmcnet.org
Subject: Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices.
We've had a GMC since 2003. Go to all the GMCMI events now. No mater were they are. Totally rebuilt 3 - 78 Royales. Two for us. One for a close friend. Now building another GMC to sell . In all this building. It's been very clear to me that GMC did a great job in engineering these coaches to high engineering standards, and the technology of the day. In changing anything. You need to evaluate if this new produce changing the original engineering parameters.
With our GMC's in the 40 to 45 years old range. We have lots of new products to install. Some products enhance the original GM designs. Mostly because of new technology that wasn't available, or known in the 70's. Electronic Fuel Injection ( EFI ) is a prime example. And our modern fuels are now formulated to be atomized by way of the pressures that EFI provides. We have EFI/computer, spark control systems in the Howell EFI package. I'm looking forward to the day when we can remove the camshaft from our engines. And have the valves controlled electronically. This will be a terrific enhancement in the way of better valve timing. Mileage, and torque. We now have an electronically controlled fan clutch to help stabilize our engine temps more closely. This is done by sensing engine temps. Not air temps from the radiator. Engine electric water pumps can't be far away. We're removing the failure prone tank selector switch in exchange for a two pump fuel delivery system. We have our original front wheel bearings now that will never have to be remove to get new grease put in them. Thus a true lifetime bearing now. We have some new air bags Due to the original bags not being produced. We have the Quad bag system that has some pros/cons ( Pros. Is a little more stable on the road. Can maintain ride height if a bag fails. Cons. Doesn't handle speed bumps as well. ) And maintains the original rear suspension design. Rear disc brakes to enhance braking. The original rear drum brakes did a good job. But you had to adjust them each year. Jim K at Applied came up with the 3:70 final drive. Fantastic improvement. This list is too long to continue.
Next are two ideas that don't fallow SAE ( Society of Automotive Engineers ) practices.
1 All wheels are made with what's called. Offset. This offset is to place the center of the tire in a very particular position over the Inter/outer wheel bearings. This position is in reference to the load carrying capacity of each of the inter/outer wheel bearings. Our rims have a lot of offset. This can be seen in comparing standard pickup rims to ours. Our lug nuts are out at the tire side wall. Pickup lug nuts are closer to being between the sidewalls. Most cars, and trucks don't have the front and rear tires travel in the same track. Our GMC's have the rear tires tracking wider then the front. There are spacers on the market that will space the front tires out to match the rear tire track. These spacers put excessive loads on the outer front wheel bearings. Pot holes/rough road surfaces acerbate this issue greatly. I would never ever install these on any GMC.
2 An SAE standard has stated for decades that upper/lower A frames should be parallel to each other for proper suspension geometry. With the 1 ton kit. The A frames are no longer parallel to each other. It's said that the 1 ton has a lifetime bearing. The lifetime is over when the bearing fails. Not the life of your GMC, or YOU. SORRY. We have lifetime bearings now that we can lube. And comply to SAE standards. Most original bearing have gone well over 100,000 miles over 40 some years before ever being serviced. From what I've been told. The GM 1 ton bearings are larger. This maybe true. But this 1 ton kit also has the spacer that's listed above. ( I believe the 1 ton spacer is even longer. ) GM never intended for the 1 ton bearing to be loaded in this over loaded condition all the time. ( As a note.) We just talked about overloading the rear tires/ bearings by running 3 tires with the Quad bag. At least the rear wheel bearing weren't being run with the bearings improperly loaded. I put a 1 ton unit in a friends GMC. Now wish that I wouldn't have done it. I know of many owners that have installed the 1 ton. Talk about the improved handling. But most of those GMC's were riding on worn out parts. Dave Lenzi IS the true expert on brakes/suspension components for GMC's. There is no debate on his knowledge. At the next GMCMI event. Ask Dave for a short version of his opinion of the 1 ton. I'm not saying. Don't install the 1 ton. I'm just saying that this is some info on it. It's your GMC. I'll personally go with SAE approved design applications.
GM did a lot of R/D in make our GMC's. We need to keep their design reasoning in mine. Items like electronic fuel injection WITH spark control. That is a technology that wasn't available back then. It's an excellent upgrade that should be at the top of every GMC owners list. I was slow to get mine on. Love it. My 2 cent on the topic. Bob Dunahugh
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332101 is a reply to message #332098] |
Tue, 15 May 2018 11:35 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
|
Senior Member |
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12,000 pound, 6 wheels down, underpowered front wheel drive, high center
of balance motorhomes do not handle even remotely like a 1250 pound mid
engined rear wheel drive race car with 700 horsepower. All that
hypothetical crap about a-arms must be perpendicular to the racing surface
goes out the window.
The average 60+ year old driver of motor homes cares about wind steer,
tire tread life, driver comfort, etc. They like straight line braking to be
comparable to modern autos that they share the road with. Just my opinion.
Your might vary.
Jim Hupy
Salem, Or
78 GMC ROYALE 403
On Tue, May 15, 2018, 9:21 AM Fred wrote:
> Richard Denney wrote on Tue, 15 May 2018 10:35
>> It means camber will increase (slightly) with jounce,
>
>
> negative or positive camber? and by using the word 'jounce' do you mean
> upward motion?
>
> if negative camber increases with upward motion, it wouldnt be as bad as
> positive camber increasing with upward motion IMO but if it is a drastic
> change eitherway (more than one degree) it would upset traction. actually
> any change will upset traction but a minor amount might be acceptable.
>
> does anyone know how much difference there is and if one of the ball
> joints could be relocated to correct it?
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332105 is a reply to message #332101] |
Tue, 15 May 2018 12:24 |
 |
Matt Colie
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
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Senior Member |
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|
James Hupy wrote on Tue, 15 May 2018 12:3512,000 pound, 6 wheels down, underpowered front wheel drive, high center of balance motorhomes do not handle even remotely like a 1250 pound mid engined rear wheel drive race car with 700 horsepower. All that hypothetical crap about a-arms must be perpendicular to the racing surface goes out the window.
The average 60+ year old driver of motor homes cares about wind steer, tire tread life, driver comfort, etc. They like straight line braking to be
comparable to modern autos that they share the road with. Just my opinion.
Your might vary.
Jim Hupy
I will start be saying that, yes, I drove race cars and I was a ride and handling consultant to four OEs as an when with a contract test group, so I thought I might be overly critical. That went out the window when Mary was driving another coach as an instructor for during the lady's driving school. She reported confidentially to me that the coach she drove misbehaved on a hard corner. As a favor I intended to warn the owner. We got to talking and I got to drive the coach. It had a 1-ton mod and it did have nice brakes, but it also had a different handling issue when pushed into a corner. I knew from experience that it was caused by adverse camber. This might be mitigated if one was to install a much heavier sway (really it is an anti-roll) bar in the front so there is less differential change in any cornering situation.
Matt
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332106 is a reply to message #332101] |
Tue, 15 May 2018 12:22 |
johnd01
Messages: 354
Registered: July 2017
Location: Sacrameot
Karma: -1
|
Senior Member |
|
|
I am more concerned with front wheel bearing life. Do we really have to
service the front bearings at 3500 miles? I do not remember ever having a
vehicle that needed repacking less than 50k miles.
As for locking up all 6 wheels, the fact that you can lock them all up is
one thing but the real key is they should all lock up at the same time. The
pole-vault effect is one thing but the real problem is that it unloads the
back wheels. Replacing the back wheel cylinder with a smaller one that
locks it up just after the center axel locks up would be a more
cost-effective solution. The key is balance between braking and traction,
where traction is proportional to the dynamic loading while braking. With
the long wheelbase, we do not get as much load transfer as a car would get.
The main transfer we get is from the back to the center wheels.
75 Avion
Sacramento CA
On Tue, May 15, 2018 at 9:35 AM, James Hupy wrote:
> 12,000 pound, 6 wheels down, underpowered front wheel drive, high center
> of balance motorhomes do not handle even remotely like a 1250 pound mid
> engined rear wheel drive race car with 700 horsepower. All that
> hypothetical crap about a-arms must be perpendicular to the racing surface
> goes out the window.
> The average 60+ year old driver of motor homes cares about wind steer,
> tire tread life, driver comfort, etc. They like straight line braking to be
> comparable to modern autos that they share the road with. Just my opinion.
> Your might vary.
> Jim Hupy
> Salem, Or
> 78 GMC ROYALE 403
>
> On Tue, May 15, 2018, 9:21 AM Fred wrote:
>
>> Richard Denney wrote on Tue, 15 May 2018 10:35
>>> It means camber will increase (slightly) with jounce,
>>
>>
>> negative or positive camber? and by using the word 'jounce' do you mean
>> upward motion?
>>
>> if negative camber increases with upward motion, it wouldnt be as bad as
>> positive camber increasing with upward motion IMO but if it is a drastic
>> change eitherway (more than one degree) it would upset traction. actually
>> any change will upset traction but a minor amount might be acceptable.
>>
>> does anyone know how much difference there is and if one of the ball
>> joints could be relocated to correct it?
>>
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
*John Phillips*
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Johnd01
John Phillips
Avion A2600 TZE064V101164
Rancho Cordova, CA (Sacramento)
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332107 is a reply to message #332106] |
Tue, 15 May 2018 12:33 |
Keith V
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
|
Senior Member |
|
|
John Phillips wrote:
"As for locking up all 6 wheels, the fact that you can lock them all up is
one thing but the real key is they should all lock up at the same time. "
OMG no, The rear wheels should not lock up until after the front ones, unless you like driving backwards and upside down
________________________________
From: Gmclist on behalf of John Phillips
Sent: Tuesday, May 15, 2018 12:22 PM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices.
I am more concerned with front wheel bearing life. Do we really have to
service the front bearings at 3500 miles? I do not remember ever having a
vehicle that needed repacking less than 50k miles.
As for locking up all 6 wheels, the fact that you can lock them all up is
one thing but the real key is they should all lock up at the same time. The
pole-vault effect is one thing but the real problem is that it unloads the
back wheels. Replacing the back wheel cylinder with a smaller one that
locks it up just after the center axel locks up would be a more
cost-effective solution. The key is balance between braking and traction,
where traction is proportional to the dynamic loading while braking. With
the long wheelbase, we do not get as much load transfer as a car would get.
The main transfer we get is from the back to the center wheels.
75 Avion
Sacramento CA
On Tue, May 15, 2018 at 9:35 AM, James Hupy wrote:
> 12,000 pound, 6 wheels down, underpowered front wheel drive, high center
> of balance motorhomes do not handle even remotely like a 1250 pound mid
> engined rear wheel drive race car with 700 horsepower. All that
> hypothetical crap about a-arms must be perpendicular to the racing surface
> goes out the window.
> The average 60+ year old driver of motor homes cares about wind steer,
> tire tread life, driver comfort, etc. They like straight line braking to be
> comparable to modern autos that they share the road with. Just my opinion.
> Your might vary.
> Jim Hupy
> Salem, Or
> 78 GMC ROYALE 403
>
> On Tue, May 15, 2018, 9:21 AM Fred wrote:
>
>> Richard Denney wrote on Tue, 15 May 2018 10:35
>>> It means camber will increase (slightly) with jounce,
>>
>>
>> negative or positive camber? and by using the word 'jounce' do you mean
>> upward motion?
>>
>> if negative camber increases with upward motion, it wouldnt be as bad as
>> positive camber increasing with upward motion IMO but if it is a drastic
>> change eitherway (more than one degree) it would upset traction. actually
>> any change will upset traction but a minor amount might be acceptable.
>>
>> does anyone know how much difference there is and if one of the ball
>> joints could be relocated to correct it?
>>
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
*John Phillips*
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Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332108 is a reply to message #332106] |
Tue, 15 May 2018 12:46 |
johnd01
Messages: 354
Registered: July 2017
Location: Sacrameot
Karma: -1
|
Senior Member |
|
|
The traction thing is a function of how much weight there is on the drive
wheels. In a front wheel drive car, the front wheels have more weight than
the rear unless you have a heavy load. Front wheel drive cars have better
traction characteristics than rear wheel drive. We have about 4k of 12k
lbs on the front axle. If we changed the system to only drive the center
wheels like we had a tag axle we would have the same problem. Tag axle
systems get away with driving the axle with the most load and in most cases
can unload the tag. Have 1/3 of the load on the drive wheels puts this MH
to a disadvantage compared to on with 2/3.
There may be other factors but these are the ones I see.
On Tue, May 15, 2018 at 10:22 AM, John Phillips
wrote:
> I am more concerned with front wheel bearing life. Do we really have to
> service the front bearings at 3500 miles? I do not remember ever having a
> vehicle that needed repacking less than 50k miles.
> As for locking up all 6 wheels, the fact that you can lock them all up is
> one thing but the real key is they should all lock up at the same time. The
> pole-vault effect is one thing but the real problem is that it unloads the
> back wheels. Replacing the back wheel cylinder with a smaller one that
> locks it up just after the center axel locks up would be a more
> cost-effective solution. The key is balance between braking and traction,
> where traction is proportional to the dynamic loading while braking. With
> the long wheelbase, we do not get as much load transfer as a car would get.
> The main transfer we get is from the back to the center wheels.
>
> 75 Avion
> Sacramento CA
>
>
>
> On Tue, May 15, 2018 at 9:35 AM, James Hupy wrote:
>
>> 12,000 pound, 6 wheels down, underpowered front wheel drive, high center
>> of balance motorhomes do not handle even remotely like a 1250 pound mid
>> engined rear wheel drive race car with 700 horsepower. All that
>> hypothetical crap about a-arms must be perpendicular to the racing surface
>> goes out the window.
>> The average 60+ year old driver of motor homes cares about wind
>> steer,
>> tire tread life, driver comfort, etc. They like straight line braking to
>> be
>> comparable to modern autos that they share the road with. Just my opinion.
>> Your might vary.
>> Jim Hupy
>> Salem, Or
>> 78 GMC ROYALE 403
>>
>> On Tue, May 15, 2018, 9:21 AM Fred wrote:
>>
>>> Richard Denney wrote on Tue, 15 May 2018 10:35
>>>> It means camber will increase (slightly) with jounce,
>>>
>>>
>>> negative or positive camber? and by using the word 'jounce' do you mean
>>> upward motion?
>>>
>>> if negative camber increases with upward motion, it wouldnt be as bad as
>>> positive camber increasing with upward motion IMO but if it is a drastic
>>> change eitherway (more than one degree) it would upset traction.
>> actually
>>> any change will upset traction but a minor amount might be acceptable.
>>>
>>> does anyone know how much difference there is and if one of the ball
>>> joints could be relocated to correct it?
>>>
>>>
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
>
> --
>
> *John Phillips*
>
--
*John Phillips*
_______________________________________________
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Unsubscribe or Change List Options:
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Johnd01
John Phillips
Avion A2600 TZE064V101164
Rancho Cordova, CA (Sacramento)
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332110 is a reply to message #332108] |
Tue, 15 May 2018 12:58 |
johnd01
Messages: 354
Registered: July 2017
Location: Sacrameot
Karma: -1
|
Senior Member |
|
|
Keith,
The key is if they are balanced they should all lock up at the same time.
There is no way to get them that balanced. The key is you do not lock them
up at all. Locked up is not good practice but only a test to see if you can
do it. Max brake is just before lockup. Ideally the center then the front
and last the back axle. I did state the middle should lockup before the
back wheels
On Tue, May 15, 2018 at 10:46 AM, John Phillips
wrote:
> The traction thing is a function of how much weight there is on the drive
> wheels. In a front wheel drive car, the front wheels have more weight than
> the rear unless you have a heavy load. Front wheel drive cars have better
> traction characteristics than rear wheel drive. We have about 4k of 12k
> lbs on the front axle. If we changed the system to only drive the center
> wheels like we had a tag axle we would have the same problem. Tag axle
> systems get away with driving the axle with the most load and in most cases
> can unload the tag. Have 1/3 of the load on the drive wheels puts this MH
> to a disadvantage compared to on with 2/3.
> There may be other factors but these are the ones I see.
>
>
> On Tue, May 15, 2018 at 10:22 AM, John Phillips
> wrote:
>
>> I am more concerned with front wheel bearing life. Do we really have to
>> service the front bearings at 3500 miles? I do not remember ever having a
>> vehicle that needed repacking less than 50k miles.
>> As for locking up all 6 wheels, the fact that you can lock them all up is
>> one thing but the real key is they should all lock up at the same time. The
>> pole-vault effect is one thing but the real problem is that it unloads the
>> back wheels. Replacing the back wheel cylinder with a smaller one that
>> locks it up just after the center axel locks up would be a more
>> cost-effective solution. The key is balance between braking and traction,
>> where traction is proportional to the dynamic loading while braking. With
>> the long wheelbase, we do not get as much load transfer as a car would get.
>> The main transfer we get is from the back to the center wheels.
>>
>> 75 Avion
>> Sacramento CA
>>
>>
>>
>> On Tue, May 15, 2018 at 9:35 AM, James Hupy wrote:
>>
>>> 12,000 pound, 6 wheels down, underpowered front wheel drive, high center
>>> of balance motorhomes do not handle even remotely like a 1250 pound mid
>>> engined rear wheel drive race car with 700 horsepower. All that
>>> hypothetical crap about a-arms must be perpendicular to the racing
>>> surface
>>> goes out the window.
>>> The average 60+ year old driver of motor homes cares about wind
>>> steer,
>>> tire tread life, driver comfort, etc. They like straight line braking to
>>> be
>>> comparable to modern autos that they share the road with. Just my
>>> opinion.
>>> Your might vary.
>>> Jim Hupy
>>> Salem, Or
>>> 78 GMC ROYALE 403
>>>
>>> On Tue, May 15, 2018, 9:21 AM Fred wrote:
>>>
>>>> Richard Denney wrote on Tue, 15 May 2018 10:35
>>>> > It means camber will increase (slightly) with jounce,
>>>>
>>>>
>>>> negative or positive camber? and by using the word 'jounce' do you mean
>>>> upward motion?
>>>>
>>>> if negative camber increases with upward motion, it wouldnt be as bad
>>> as
>>>> positive camber increasing with upward motion IMO but if it is a
>>> drastic
>>>> change eitherway (more than one degree) it would upset traction.
>>> actually
>>>> any change will upset traction but a minor amount might be acceptable.
>>>>
>>>> does anyone know how much difference there is and if one of the ball
>>>> joints could be relocated to correct it?
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> GMCnet mailing list
>>>> Unsubscribe or Change List Options:
>>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>>
>>
>>
>> --
>>
>> *John Phillips*
>>
>
>
>
> --
>
> *John Phillips*
>
--
*John Phillips*
_______________________________________________
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Unsubscribe or Change List Options:
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Johnd01
John Phillips
Avion A2600 TZE064V101164
Rancho Cordova, CA (Sacramento)
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332116 is a reply to message #332111] |
Tue, 15 May 2018 14:43 |
Jimmy_Bonez
Messages: 105
Registered: September 2017
Location: NH
Karma: 0
|
Senior Member |
|
|
Excuse my ignorance to this topic but I am green to the GMC motorhome community. I’ve learned a few things in the short amount of time we’ve owned one but this topic of which front end to run always seems to be a hot topic. Again I apologize if these questions sound dumb. But why is it that there are only 2 options to solve any of the above named problems with our front ends. With the amount of builders out there and suspension “experts” there should be more options. Heavy duty control arms are abundant not just relegated to the one ton gm ones that people are using. Along with aftermarket suspension components that can accommodate any number of scenarios. Again I’m learning as I go and have had the opportunity to build a few suspension systems in custom cars and trucks but nothing on the scale of our rigs. Maybe some day when we park ours I’ll have a chance to dive in but until then I’ll differ to the guys that have tried and experimented with any number of components.
Sent from my iPhone
> On May 15, 2018, at 12:10 PM, Fred wrote:
>
> johnd01 wrote on Tue, 15 May 2018 12:46
>> The traction thing is a function of how much weight there is on the drive
>> wheels. In a front wheel drive car, the front wheels have more weight than
>> the rear unless you have a heavy load. Front wheel drive cars have better
>> traction characteristics than rear wheel drive. We have about 4k of 12k
>> lbs on the front axle. If we changed the system to only drive the center
>> wheels like we had a tag axle we would have the same problem. Tag axle
>> systems get away with driving the axle with the most load and in most cases
>> can unload the tag. Have 1/3 of the load on the drive wheels puts this MH
>> to a disadvantage compared to on with 2/3.
>> There may be other factors but these are the ones I see.
>
>
> many other factors. but the incorrect geometry of the 1-ton would seem to make an already traction challenged front drive even worse.
>
> but can the 1-ton geometry be corrected with ball joint relocation by modifying one or both control arms is my biggest question. if the geometry cant
> be correct, Im not interested and wont be considering coaches that have the 1-ton front.
>
> see, when the camber changes, it moves the tire laterally and that starts the loss of traction then it gets continued by the drive forces. once the
> traction is 'broke' its nearly impossible to get it back.
>
> I would really like to have one without the difficult wheel bearings but Id rather have one that can negotiate difficult paved surfaces and minor
> offroad the best. drive traction is obviously an issue before any incorrect geometry.
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
_______________________________________________
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Unsubscribe or Change List Options:
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Jim DeMellia and Jen Radefeld and our cat Ickis
NH natives
1975 GMC “Palm Beach” ,455, her names Linda
Full time RVers exploring the beautiful and unusual parts of the country.
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| Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices. [message #332119 is a reply to message #332110] |
Tue, 15 May 2018 15:13 |
Keith V
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
|
Senior Member |
|
|
John
Nope they should not lock up at the same time. ( non racing applications )
Agreed that Lockup is not desirable but can happen, and is pretty hard to do on a stock-ish system
Good luck getting the middle to lockup first, and again it shouldn't, the front should lock first.
If the backs lock first you will swap ends and loose control, if the front locks first you will plow a little until you release the pedal
________________________________
From: Gmclist on behalf of John Phillips
Sent: Tuesday, May 15, 2018 12:58 PM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Tid Bit. When making changes to your GMC. Does that change differ from proven automotive engineering practices.
Keith,
The key is if they are balanced they should all lock up at the same time.
There is no way to get them that balanced. The key is you do not lock them
up at all. Locked up is not good practice but only a test to see if you can
do it. Max brake is just before lockup. Ideally the center then the front
and last the back axle. I did state the middle should lockup before the
back wheels
On Tue, May 15, 2018 at 10:46 AM, John Phillips
wrote:
> The traction thing is a function of how much weight there is on the drive
> wheels. In a front wheel drive car, the front wheels have more weight than
> the rear unless you have a heavy load. Front wheel drive cars have better
> traction characteristics than rear wheel drive. We have about 4k of 12k
> lbs on the front axle. If we changed the system to only drive the center
> wheels like we had a tag axle we would have the same problem. Tag axle
> systems get away with driving the axle with the most load and in most cases
> can unload the tag. Have 1/3 of the load on the drive wheels puts this MH
> to a disadvantage compared to on with 2/3.
> There may be other factors but these are the ones I see.
>
>
> On Tue, May 15, 2018 at 10:22 AM, John Phillips
> wrote:
>
>> I am more concerned with front wheel bearing life. Do we really have to
>> service the front bearings at 3500 miles? I do not remember ever having a
>> vehicle that needed repacking less than 50k miles.
>> As for locking up all 6 wheels, the fact that you can lock them all up is
>> one thing but the real key is they should all lock up at the same time. The
>> pole-vault effect is one thing but the real problem is that it unloads the
>> back wheels. Replacing the back wheel cylinder with a smaller one that
>> locks it up just after the center axel locks up would be a more
>> cost-effective solution. The key is balance between braking and traction,
>> where traction is proportional to the dynamic loading while braking. With
>> the long wheelbase, we do not get as much load transfer as a car would get.
>> The main transfer we get is from the back to the center wheels.
>>
>> 75 Avion
>> Sacramento CA
>>
>>
>>
>> On Tue, May 15, 2018 at 9:35 AM, James Hupy wrote:
>>
>>> 12,000 pound, 6 wheels down, underpowered front wheel drive, high center
>>> of balance motorhomes do not handle even remotely like a 1250 pound mid
>>> engined rear wheel drive race car with 700 horsepower. All that
>>> hypothetical crap about a-arms must be perpendicular to the racing
>>> surface
>>> goes out the window.
>>> The average 60+ year old driver of motor homes cares about wind
>>> steer,
>>> tire tread life, driver comfort, etc. They like straight line braking to
>>> be
>>> comparable to modern autos that they share the road with. Just my
>>> opinion.
>>> Your might vary.
>>> Jim Hupy
>>> Salem, Or
>>> 78 GMC ROYALE 403
>>>
>>> On Tue, May 15, 2018, 9:21 AM Fred wrote:
>>>
>>>> Richard Denney wrote on Tue, 15 May 2018 10:35
>>>> > It means camber will increase (slightly) with jounce,
>>>>
>>>>
>>>> negative or positive camber? and by using the word 'jounce' do you mean
>>>> upward motion?
>>>>
>>>> if negative camber increases with upward motion, it wouldnt be as bad
>>> as
>>>> positive camber increasing with upward motion IMO but if it is a
>>> drastic
>>>> change eitherway (more than one degree) it would upset traction.
>>> actually
>>>> any change will upset traction but a minor amount might be acceptable.
>>>>
>>>> does anyone know how much difference there is and if one of the ball
>>>> joints could be relocated to correct it?
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> GMCnet mailing list
>>>> Unsubscribe or Change List Options:
>>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>>
>>> _______________________________________________
>>> GMCnet mailing list
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Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
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