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1 ton question [message #268041] Mon, 22 December 2014 17:28 Go to next message
roy1 is currently offline  roy1   United States
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I put the 1ton front end in my coach. On my first trip with it installed I noticed on hard acceleration it seems to shudder going into 2nd on a hard shift at full throttle. The main problem I see is after traveling 600 miles going up a steep grade about an 8 to 10 % grade in low gear with my Toyota in tow the front end gets real squirley like it is coming off the ground and out of control . It didn't have this problem with the stock front end on this same road under the same conditions. Peter Uber mentioned he had a similar problem with his before he lost his coach. Can the ride height be modified to stop this or is this the way it will always be? This is not a nice thing , I was afraid I wasn't going to be able to get to my brothers house.

Roy Keen Minden,NV 76 X Glenbrook
Re: 1 ton question [message #268042 is a reply to message #268041] Mon, 22 December 2014 17:34 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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I have not noticed that problem Roy. I've got Manny's 1 ton. Can't speak to the other systems available. Is your ride height and alignment set correctly?

I'm trying to come up with a situation where the front end got squirrely and loose but can't come up with anything, especially at low speed. You didn't say but are you flat towing the Toyota? If you have a load on the rear bumper/frame, it could definitely make the front end feel light.


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: 1 ton question [message #268043 is a reply to message #268042] Mon, 22 December 2014 17:39 Go to previous messageGo to next message
Hal StClair   United States
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Adding the one ton will give you a little more un sprung weight and if your shocks are a little weak you might see an issue. Just guessing as I've not had a similar issue with my Manny system.
Hal


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
Re: 1 ton question [message #268048 is a reply to message #268041] Mon, 22 December 2014 19:22 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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Flat towing ,the front ride height is set according to the book. It was a few inches low in the past with the stock front end and a level coach . With the correct ride height it is lower in the rear. The problem with the squirrely front end is only under power when it is a steep incline under full throttle or close to it in low gear I don't know what it would be at greater speed as the hill is like a snake. It is like impossible to stay in one lane. When Peter told me he had this problem on a certain hill I thought it was strange but now I know what he ment. I came across a lot of 7% mountain grades yesterday climbing 8,000 ft passes yesterday and didn't have the problem just the shudder when it shifted. It is a Manny front end and the shocks are ok Bilstens. I'm thinking lowering the front ride height to a more level coach may help ?

Roy Keen Minden,NV 76 X Glenbrook
Re: 1 ton question [message #268050 is a reply to message #268041] Mon, 22 December 2014 19:41 Go to previous messageGo to next message
bwevers is currently offline  bwevers   United States
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Roy,
My coach was squirrely with the 1 ton front end installed.
It took me over a year to discover that a tie rod end was loose.
The Toronado rod ends have a 2 inch per foot taper, whereas the one ton knuckle has a 1.5 inch per foot taper.

The holes in the knuckle have to be reamed to fit the Toronado rod end.
If the hole is reamed too big, the rod end won't seat.
If the cotter pin fits in too easily, the hole could be reamed too big.

When this happens, the nut on the tie rod end will bottom on the threads before the tapered rod end is seated in hole properly.
If the big end of the tapered hole in the knuckle is too big, you could have this problem.
I put a 0.020" tapered shim in mine to tighten it up (or else replace the knuckle $$).
This made a world of difference.

Also, Jim H. said he uses a Nyloc nut instead of the castellated net on the tie-rod-end,
probably because the cotter pin won't fit when the tapered hole is tight.

Also, my handling improved when I installed Peter Huber's torsion bars and raised the front ride height.

Regards,
Bill



Bill Wevers GMC49ers, GMC Western States 1975 Glenbrook - Manny Powerdrive, OneTon 455 F Block, G heads San Jose
Re: 1 ton question [message #268051 is a reply to message #268041] Mon, 22 December 2014 19:47 Go to previous messageGo to next message
bwevers is currently offline  bwevers   United States
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The Toronado rod ends have a 2 inch per foot taper or 9.5 degree,
whereas the one ton knuckle has a 1.5 inch per foot taper or 7 degree.
I made this sketch to illustrate the problem my coach had.

http://www.gmcmhphotos.com/photos/data/6085/medium/Knuckle_Hole_.JPG


Bill Wevers GMC49ers, GMC Western States 1975 Glenbrook - Manny Powerdrive, OneTon 455 F Block, G heads San Jose

[Updated on: Tue, 23 December 2014 00:57]

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Re: 1 ton question [message #268105 is a reply to message #268041] Tue, 23 December 2014 13:15 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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The upper ball joint has a taper issue. An adapter sleeve fixed it for me.

See my video.
https://www.youtube.com/watch?v=y_WeuqNQn8g

Also check my video of the steering slop caused by excess tolerances in "new" idler and relay arms. Replaced them with Dave Lenzi products and the slop was gone.
https://www.youtube.com/watch?v=bLiySgnK1uw


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: 1 ton question [message #268107 is a reply to message #268041] Tue, 23 December 2014 16:51 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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Well I crawled under it to look closer at the ball joints and tie Rod end taper connections all look good. I did torque them when I put it together. The only ones that I put washers under the nuts were the lower ball joints . The taper part was not exposed but I needed the washers so the cotter key fit through the castrated nuts. With the truck unhooked I raised the rear airbags to level the coach and went back down the steep part of the mountain. I still needed to be in low gear for the steep incline coming back up even with no tow vehicle. I only felt a slight wobble in the steering wheel in the worst part of the grade not the scary handling it had yesterday. When I get home in a couple of months I will lower the front ride height a couple of inches and set the rear ride height for a level coach ,it may not be to spec but I can't handle these bad conditions on steep hills. It used to handle quite good when the ride height was 3" low in front even on this same steep hill. I might add there is no slop in the steering ,idler arm relay arm,or tie rods. If there any other thoughts I'm listening. Thanks for the suggestions.

Roy Keen Minden,NV 76 X Glenbrook

[Updated on: Tue, 23 December 2014 16:54]

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Re: 1 ton question [message #268113 is a reply to message #268050] Tue, 23 December 2014 19:14 Go to previous messageGo to next message
KB is currently offline  KB   United States
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Manny reams the 1ton knuckles so they have the correct taper. He had a special reamer tool made just for this.
So, if it's a Manny 1-ton kit, the taper shouldn't be an issue.

Karen
1975 26
Re: 1 ton question [message #268114 is a reply to message #268113] Tue, 23 December 2014 19:23 Go to previous messageGo to next message
KB is currently offline  KB   United States
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KB wrote on Tue, 23 December 2014 17:14
Manny reams the 1ton knuckles so they have the correct taper. He had a special reamer tool made just for this.
So, if it's a Manny 1-ton kit, the taper shouldn't be an issue.

Karen
1975 26


I should qualify that: shouldn't be an issue if the reamed depth is correct (as per Bill's drawing). If Manny did it, it's likely correct
since he's done a zillion of them and has a special tool for the job.
It is my understanding some of the other kits didn't have the knuckles reamed, so the taper could be an issue.
Re: [GMCnet] 1 ton question [message #268117 is a reply to message #268114] Tue, 23 December 2014 20:15 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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A further note on the 1 ton knuckles. The ball joint tapers are all correct
because we are using 1 ton ball joints. Where there has been an occasional
fitment issue has been on the tie rod joints. SOME, BUT NOT ALL, of the
knuckles are thicker in the area where the joint is located, and the GMC
tie rod end threaded portion is quite short. Manny has a workaround for
this. He uses a tapered reamer that is the same as the joint, and just
reams the bore a bit deeper. This allows the joint to seat further up,
giving more access to the threaded portion of the joint. It is a critical
reaming operation, and the stock joints vary a bit. So, the castellated nut
and the drilled cotter pin hole sometimes does not index. In those cases,
I fit a distressed nut. They are still torqued to the same value as the
castellated nut, and because I am a belt and suspenders kind of guy, I use
blue threadlocker as well.
Jim Hupy
Salem, Or
78 Gmc Royale 403
On Dec 23, 2014 5:24 PM, "KB" wrote:

> KB wrote on Tue, 23 December 2014 17:14
>> Manny reams the 1ton knuckles so they have the correct taper. He had a
> special reamer tool made just for this.
>> So, if it's a Manny 1-ton kit, the taper shouldn't be an issue.
>>
>> Karen
>> 1975 26
>
>
> I should qualify that: shouldn't be an issue if the reamed depth is
> correct (as per Bill's drawing). If Manny did it, it's likely correct
> since he's done a zillion of them and has a special tool for the job.
> It is my understanding some of the other kits didn't have the knuckles
> reamed, so the taper could be an issue.
>
> _______________________________________________
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Re: 1 ton question [message #268121 is a reply to message #268113] Tue, 23 December 2014 20:34 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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KB wrote on Tue, 23 December 2014 17:14
Manny reams the 1ton knuckles so they have the correct taper. He had a special reamer tool made just for this.
So, if it's a Manny 1-ton kit, the taper shouldn't be an issue.

Karen
1975 26


All the tapers on my Manny kit fit as they should have fit. My only problem is with the loss of steering control in a steep climb.


Roy Keen Minden,NV 76 X Glenbrook
Re: 1 ton question [message #268316 is a reply to message #268107] Fri, 26 December 2014 20:30 Go to previous messageGo to next message
Bob de Kruyff   United States
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roy1 wrote on Tue, 23 December 2014 15:51
Well I crawled under it to look closer at the ball joints and tie Rod end taper connections all look good. I did torque them when I put it together. The only ones that I put washers under the nuts were the lower ball joints . The taper part was not exposed but I needed the washers so the cotter key fit through the castrated nuts. With the truck unhooked I raised the rear airbags to level the coach and went back down the steep part of the mountain. I still needed to be in low gear for the steep incline coming back up even with no tow vehicle. I only felt a slight wobble in the steering wheel in the worst part of the grade not the scary handling it had yesterday. When I get home in a couple of months I will lower the front ride height a couple of inches and set the rear ride height for a level coach ,it may not be to spec but I can't handle these bad conditions on steep hills. It used to handle quite good when the ride height was 3" low in front even on this same steep hill. I might add there is no slop in the steering ,idler arm relay arm,or tie rods. If there any other thoughts I'm listening. Thanks for the suggestions.

I think you are feeling the effects of a sharp toe change curve that is inherent with the 1 Ton front end. I think that lowering the front ride height will help.


Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: 1 ton question [message #268351 is a reply to message #268041] Sat, 27 December 2014 10:23 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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If the tire /wheel centerline is outside (wider than) the steering axis through the ball joints it will dart at the point where power exceeds available traction. I have never studied a 1ton up close, never worked on or driven one, and don't really understand the reason for the big spacers. I'm just making the stearing axis statement based on photos. I know it increases the load on the Tbars with a longer lever arm effective length, so someone please prove ne wrong.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: 1 ton question [message #268374 is a reply to message #268351] Sat, 27 December 2014 16:05 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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JohnL455 wrote on Sat, 27 December 2014 08:23
If the tire /wheel centerline is outside (wider than) the steering axis through the ball joints it will dart at the point where power exceeds available traction. I have never studied a 1ton up close, never worked on or driven one, and don't really understand the reason for the big spacers. I'm just making the stearing axis statement based on photos. I know it increases the load on the Tbars with a longer lever arm effective length, so someone please prove ne wrong.


As Bob suggested it definitely improved when the nose was lower I don't care for the darting around and it should be easier on the torsion bars as they won't be twisted as tight.The spacers need to be there or you would need probibly 20" rims to clear the larger 1 ton rotor caliper set up.


Roy Keen Minden,NV 76 X Glenbrook
Re: [GMCnet] 1 ton question [message #268399 is a reply to message #268351] Sat, 27 December 2014 21:51 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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John,

Here's a drawing of the OEM hub / knuckle showing the steering axis. I've made the statement:

It appears to me that if you extend the steering axis (line through center of upper and lower ball joints) it will come close to
going through the center of the tire contact patch.

http://www.gmcmhphotos.com/photos/aa-miscellaneous-photos/p56759-steering-axis.html

The spacer that the 1 Ton uses will shift the wheel / tire outwards.

I am loathe to comment on the effects of that as I do not have a 1 ton front end and have never driven a GMC with a 1 ton front end.
Empirical engineering says it's OK as the people that have them have not complained about what you've noted.

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426

-----Original Message-----
From: John R. Lebetski

If the tire /wheel centerline is outside (wider than) the steering axis through the ball joints it will dart at the point where
power exceeds
available traction. I have never studied a 1ton up close, never worked on or driven one, and don't really understand the reason for
the big spacers.

I'm just making the stearing axis statement based on photos. I know it increases the load on the Tbars with a longer lever arm
effective length, so someone please prove ne wrong.
--
John

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: 1 ton question [message #268416 is a reply to message #268041] Sun, 28 December 2014 07:52 Go to previous messageGo to next message
rcjordan   United States
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> not complained

With only 100 miles or so of test-driving (in and around Orlando) the Royale fitted with the Manny 1-ton and Huber's beefed-up torsion bars, the results so far have been excellent.


SOLD 77 Royale Coachmen Side Dry Bath
76 Birchaven Coachmen Side Wet Bath
76 Eleganza
Elizabeth City, NC
Re: [GMCnet] 1 ton question [message #268430 is a reply to message #268416] Sun, 28 December 2014 09:31 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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And here are a couple of drawings that show there is almost no difference
Drawings by Stan
https://www.facebook.com/photo.php?fbid=10204172125878154&set=o.183025891821956&type=3&theater

Erf

On Saturday, December 27, 2014, Robert Mueller wrote:

> John,
>
> Here's a drawing of the OEM hub / knuckle showing the steering axis. I've
> made the statement:
>
> It appears to me that if you extend the steering axis (line through center
> of upper and lower ball joints) it will come close to
> going through the center of the tire contact patch.
>
>
> http://www.gmcmhphotos.com/photos/aa-miscellaneous-photos/p56759-steering-axis.html
>
> The spacer that the 1 Ton uses will shift the wheel / tire outwards.
>
> I am loathe to comment on the effects of that as I do not have a 1 ton
> front end and have never driven a GMC with a 1 ton front end.
> Empirical engineering says it's OK as the people that have them have not
> complained about what you've noted.
>
> Regards,
> Rob M.
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
>
> -----Original Message-----
> From: John R. Lebetski
>
> If the tire /wheel centerline is outside (wider than) the steering axis
> through the ball joints it will dart at the point where
> power exceeds
> available traction. I have never studied a 1ton up close, never worked on
> or driven one, and don't really understand the reason for
> the big spacers.
>
> I'm just making the stearing axis statement based on photos. I know it
> increases the load on the Tbars with a longer lever arm
> effective length, so someone please prove ne wrong.
> --
> John
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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“Give a man a fish; you have fed him for today --- give him a URL and
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Re: [GMCnet] 1 ton question [message #268437 is a reply to message #268430] Sun, 28 December 2014 10:26 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
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Mr ERFisher wrote on Sun, 28 December 2014 09:31
And here are a couple of drawings that show there is almost no difference
Drawings by Stan
https://www.facebook.com/photo.php?fbid=10204172125878154&set=o.183025891821956&type=3&theater

Erf

On Saturday, December 27, 2014, Robert Mueller wrote:

> John,
>
> Here's a drawing of the OEM hub / knuckle showing the steering axis. I've
> made the statement:
>
> It appears to me that if you extend the steering axis (line through center
> of upper and lower ball joints) it will come close to
> going through the center of the tire contact patch.
>
>
> http://www.gmcmhphotos.com/photos/aa-miscellaneous-photos/p56759-steering-axis.html
>
> The spacer that the 1 Ton uses will shift the wheel / tire outwards.
>
> I am loathe to comment on the effects of that as I do not have a 1 ton
> front end and have never driven a GMC with a 1 ton front end.
> Empirical engineering says it's OK as the people that have them have not
> complained about what you've noted.
>
> Regards,
> Rob M.
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
>
> -----Original Message-----
> From: John R. Lebetski
>
> If the tire /wheel centerline is outside (wider than) the steering axis
> through the ball joints it will dart at the point where
> power exceeds
> available traction. I have never studied a 1ton up close, never worked on
> or driven one, and don't really understand the reason for
> the big spacers.
>
> I'm just making the stearing axis statement based on photos. I know it
> increases the load on the Tbars with a longer lever arm
> effective length, so someone please prove ne wrong.
> --
> John
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>


--
Gene Fisher -- 74-23,77PB/ore/ca
"Give a man a fish; you have fed him for today --- give him a URL and
-------
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http://gmcmotorhome.info/APC.html
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if that drawing is accurate, it looks like a big difference to me.


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: [GMCnet] 1 ton question [message #268442 is a reply to message #268437] Sun, 28 December 2014 11:35 Go to previous messageGo to previous message
Ken Henderson is currently offline  Ken Henderson   United States
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On the other hand, I was surprised at how little difference there is.

If the drawings came from anyone except Stan (I'm assuming Edwards), I'd
doubt the accuracy since there's no dimensional difference between the
A-arms -- I don't see where the 16*-11*=5* difference in the steering axis
comes from. The knuckles are obviously sufficiently different to account
for it, but I'd have thought that when we adjust back to the same camber,
that would be negated.

Since Stan very likely did the drawings before he did the modification (he
did his own), I'm confident they're accurate.

Ken H.


On Sun, Dec 28, 2014 at 11:26 AM, Keith V wrote:
​...​


>
> if
> that drawing is accurate, it looks like a big difference to me.
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
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