GMCforum
For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.

Home » Public Forums » GMCnet » interesting front alignment
interesting front alignment [message #100444] Mon, 20 September 2010 17:38 Go to next message
fred v is currently offline  fred v   United States
Messages: 999
Registered: April 2006
Location: pensacola, fl.
Karma: 0
Senior Member
i have had a pull to the right for the last 6 months (haven't driven much). i went to my favorite shop and they found the caster and camber very different from side to side. anyway they fixed that and drove and found it still pulled to the right. they swapped the front tires and then it pulled to the left! they then swapped the fronts to the center and it drove great.

i don't understand why a tire would do this. the guy looked closely at the tires and could see no problems with them.
confused,


Fred V
'77 Royale RB 455
P'cola, Fl
Re: interesting front alignment [message #100453 is a reply to message #100444] Mon, 20 September 2010 19:05 Go to previous messageGo to next message
kingd is currently offline  kingd   Canada
Messages: 592
Registered: June 2004
Karma: 2
Senior Member
"Something" is going on with the belts in one of the tires that were on the front. From my experience and converstions with the tire technicians where my son works, you have an upcoming tire failre(Assuming this "pulling" has not been going on since the tires were new in which case there is a manufacturing defect in that the belts are not located properly) If this a new situation, I'd experiment(carefully) to determine which used to be front tire it really is, and then scrap that tire, yes I know about the espense, but cheaper than an on the road failure.

DAVE KING


DAVE KING lurker, wannabe Toronto, Ontario, Canada
Re: [GMCnet] interesting front alignment [message #100461 is a reply to message #100453] Mon, 20 September 2010 19:24 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
If that tire comes apart on the rear, they usually tear the hell out of the
skirt, air bag hoses, the inner fender well and the side of the coach. It
sounds like you have a cord separation condition going on. Usually costs
thousands to fix the coach if you include paint. Makes a new $150.00 tire
seem cheap to me. Good insurance to replace both of the previous fronts with
new ones IMHO.
Jim Hupy
Salem, OR
78 Royale 403

On Mon, Sep 20, 2010 at 5:05 PM, Dave King <kingd@sympatico.ca> wrote:

>
>
> "Something" is going on with the belts in one of the tires that were on the
> front. From my experience and converstions with the tire technicians where
> my son works, you have an upcoming tire failre(Assuming this "pulling" has
> not been going on since the tires were new in which case there is a
> manufacturing defect in that the belts are not located properly) If this a
> new situation, I'd experiment(carefully) to determine which used to be front
> tire it really is, and then scrap that tire, yes I know about the espense,
> but cheaper than an on the road failure.
>
> DAVE KING
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Re: interesting front alignment [message #100475 is a reply to message #100444] Mon, 20 September 2010 20:33 Go to previous messageGo to next message
g.winger is currently offline  g.winger   United States
Messages: 792
Registered: February 2008
Location: Warrenton,Missouri
Karma: 0
Senior Member
I maintain the machines that do over 400 alignments per day. The MOST important thing to do BEFORE you drop off a vehicle for an alignment job is to check your own tire pressure. Low tire pressure will cause to much CAMBER and just mess up everything. I watched an engineer order a repairman change a rearend because of too much camber. After the swap the camber was unchanged. Suprise!!! Low tire pressure. Used the same tires. They went and swapped tires and the camber changed. Correct pressure. Remember,,,I maintain the machines but don't work on the product. The regular alignment engineer was off that day.
Re: interesting front alignment [message #100480 is a reply to message #100444] Mon, 20 September 2010 21:02 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
On a car it would be:
1 check all the parts for damage (bent) and wear (play) and missing grease boots, rubber bushing deterioration, corrosion etc.
2 Check the tire pressure (same gauge on all 4 corners please as they are all off a few #)and check tire wear patterns and condition (sort of like reading spark plugs in the old days)
3 check the ride height
4 check the trunk for junk
5 1/2 tank of gas (150# sand bags in the drivers seat if you are realy anal) Drive the car to get a base line for handling issues.
6 then do the alignment
7 drive the car to see how it behaves now and if it is neutral.

How many techs follow the above steps and just chase problems in a circle by jumping right in to the alignment?
I love when Jiffy Lube uses one airhose and gauge on the left and a different setup on the right side. Check your air pressure with a real guage when you get home and see how far off it is--- but that's a whole nother issue.


John Lebetski
Woodstock, IL
77 Eleganza II
Re: interesting front alignment [message #100483 is a reply to message #100444] Mon, 20 September 2010 21:10 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
Messages: 2629
Registered: April 2006
Karma: 18
Senior Member
fred v wrote on Mon, 20 September 2010 18:38

i have had a pull to the right for the last 6 months (haven't driven much). i went to my favorite shop and they found the caster and camber very different from side to side. anyway they fixed that and drove and found it still pulled to the right. they swapped the front tires and then it pulled to the left! they then swapped the fronts to the center and it drove great.

i don't understand why a tire would do this. the guy looked closely at the tires and could see no problems with them.
confused,









Sir: as to the pulling to the right after alignment.. happened to me with the wifes car. Swaped the 2 front tires and pulling was gone? It is still doing good??

The previous front alignment being out could have been the top arms not torqued to 95 lb. That is a lot, the factory bolts are hardned fine thread with long nuts and will take the torque, the replacements are course thread and not hardned. Just something to look for.


C. Boyd
76 Crestmont
East Tennessee
Re: [GMCnet] interesting front alignment [message #100489 is a reply to message #100483] Mon, 20 September 2010 21:50 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
While Rob was here last week, we noticed that the camber was obviously
excessive on my left wheel. Since I'd recently completed the fabrication of
two wheel alignment jigs and purchased a digital level for the purpose, we
did my first DIY alignment.

Following essentially the procedures described by Bob Drewes at the Amana
Colonies (?) GMCMI Convention, we checked the ride height and did one minor
adjustment to a front torsion bar. With several layers of PVC sheet beneath
the front tires to provide ease of movement, we set up the alignment jigs
and checked the camber. The right side was close enough to satisfy me, at
+0.3*. The left was at +4.0*!

When I loosened the adjusting bolts to correct the camber error, I found out
why it was off: The bolts were never tightened sufficiently. I'd WAG only
30 ft-lb torque on the rear bolt, maybe a little more on the front, instead
of the spec 85 ft-lb. (Bottom bolts should be 95 ft-lb.)

The positioning of the adjustment eccentrics required to set the camber to
0.0* was such that there was nothing I could do about the caster, so I
didn't even bother to check it (relieving me of the necessity to figure out
just how I'm going to measure +-20* wheel turn).

We then used Steve Ferguson's long beam method to set toe by clamping two
60" long square aluminum tubes to the horizontal bases of my alignment jigs.
With that setup, we set toe to 0", with twice the resolution we'd have had
measuring tire-to-tire.

The subsequent test drives have been very satisfying. The coach drives
better than it has after any of the 4 or 5 alignments it's had over the
years.

Today I noticed that there was a little play in the steering coupler to
steering box so I bought a new 7/16-20 x 2-1/2" Grade 8 bolt and installed
it with 70+ ft-lb torque. Play gone.

Ken H.
Americus, GA
'76 X-Birchaven w/Cad500/Howell EFI+ & EBL
www.gmcwipersetc.com
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist



Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: interesting front alignment [message #100567 is a reply to message #100483] Tue, 21 September 2010 14:36 Go to previous messageGo to next message
Bob de Kruyff   United States
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
Senior Member
One of the most common causes of pulling is the tires. If switching them side to side fixes it, leave it. This has especially been common with front wheel drive vehicles and although improved tire consistancy has improved, it's still an issue with perfectly good and new tires.

Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: interesting front alignment [message #100577 is a reply to message #100567] Tue, 21 September 2010 16:05 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
Senior Member
If a car has been pulling for very long the tires will get worn that way. when you fix the alignment issue the tires will still be messed up. You have to replace them or have them shaved or turned.

Ken, I've been doing my own alignment for 10+ years. I have a big stick caliper like thing that measures the track width. You zero it to the width of the rear of the tires, then measure the width of the front. I can easily get within 1/32 inch

For camber I have both a Longacre caster / camber gauge and a level with a micrometer on it. I think I like the level better!

for thrust line I use a snap line and some weighted objects and measure with a caliper.

I can set the car to drive straight as an arrow and compensate for which side of the freeway I like to drive on. The motor home stays mostly in the left lane, so it's set up for that. the Minivan AKA cloak of invisibility, spends a lot of time in the left lane.

It even takes less time to do the alignment that it would to drive to a shop, wait for them to do it and drive home.

I'll take on any computerized alignment shop any day. Both is quality and in speed.


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: interesting front alignment [message #100584 is a reply to message #100567] Tue, 21 September 2010 17:59 Go to previous messageGo to next message
fred v is currently offline  fred v   United States
Messages: 999
Registered: April 2006
Location: pensacola, fl.
Karma: 0
Senior Member
Bob de Kruyff wrote on Tue, 21 September 2010 14:36

One of the most common causes of pulling is the tires. If switching them side to side fixes it, leave it. This has especially been common with front wheel drive vehicles and although improved tire consistancy has improved, it's still an issue with perfectly good and new tires.

i decided to replace them rather than risk a blow out. the bad tires were Heritage AT Chinese brand. i had already replaced 4 of them for tread separation. this was the last 2.


Fred V
'77 Royale RB 455
P'cola, Fl
Re: [GMCnet] interesting front alignment [message #100588 is a reply to message #100577] Tue, 21 September 2010 18:17 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
Keith,

I'm convinced.

You mentioned one step that I left out: We started by popping a chalk line
on the floor down the center of the coach, which we determined by dropping
plumb bobs from the joints in the bumpers. I verified the accuracy of that
location in the front by measuring the center of the main (#2) cross member
from the two holes adjacent to the side rails. That measurement also
verified that the two "center" holes are NOT -- they're actually offset to
the right side (as is the engine).

With the centerline known, actually measured each way from that plane to
determine the toe. I suspect the steering improvement was as much due to
that technique as any other.

The more I searched for a bargain on a Longacre or other quality gauge, and
the more I studied, the more I was convinced that a good digital level would
do at least as good a job, and that I'd better understand the geometry after
studying the math involved in the caster calculation.

I guess the fact that most of the manufacturers seem to be going to digital
readouts, some using level modules which are detachable for other uses,
cinched my decision to use a level.

As I mentioned before, I haven't decided how I'm going to measure the +-20*
steering rotations. How do you do that (without swivel platforms)?

Oh yeah, which lane is the '29 Dodge set up for? :-)

Ken H.


On Tue, Sep 21, 2010 at 5:05 PM, Keith V <my427v8@hotmail.com> wrote:

>
> ...

Ken, I've been doing my own alignment for 10+ years. I have a big stick
> caliper like thing that measures the track width. You zero it to the width
> of the rear of the tires, then measure the width of the front. I can easily
> get within 1/32 inch
>
> For camber I have both a Longacre caster / camber gauge and a level with a
> micrometer on it. I think I like the level better!
>
> for thrust line I use a snap line and some weighted objects and measure
> with a caliper.
>
> I can set the car to drive straight as an arrow and compensate for which
> side of the freeway I like to drive on. The motor home stays mostly in the
> left lane, so it's set up for that. the Minivan AKA cloak of invisibility,
> spends a lot of time in the left lane.
>
> It even takes less time to do the alignment that it would to drive to a
> shop, wait for them to do it and drive home.
>
> I'll take on any computerized alignment shop any day. Both is quality and
> in speed.
> --
> Keith
> 69 Vette
> 29 Dodge
> 75 Royale GMC
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist



Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] interesting front alignment [message #100665 is a reply to message #100588] Wed, 22 September 2010 12:23 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
Senior Member
Ken Henderson wrote on Tue, 21 September 2010 18:17

Keith,

I'm convinced.
...

As I mentioned before, I haven't decided how I'm going to measure the +-20*
steering rotations. How do you do that (without swivel platforms)?

Oh yeah, which lane is the '29 Dodge set up for? Smile

Ken H.




For caster, which I've only done once, I just put tape on the floor and cranked the wheel over.

One thing I do, especially important on the stiffly sprung vette, is adjust, drive it around the block, then remeasure. Maybe with turn plates you wouldn't need to but even rolling the car back and forth isn't the same as a short drive.

The Vette is set up dead neutral, The '29 will be set up for the slow lane, compensated of course for my arm hanging out the window Very Happy


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: [GMCnet] interesting front alignment [message #100763 is a reply to message #100588] Thu, 23 September 2010 07:55 Go to previous messageGo to next message
fred v is currently offline  fred v   United States
Messages: 999
Registered: April 2006
Location: pensacola, fl.
Karma: 0
Senior Member
Ken Henderson wrote on Tue, 21 September 2010 18:17



As I mentioned before, I haven't decided how I'm going to measure the +-20*
steering rotations. How do you do that (without swivel platforms)?

Oh yeah, which lane is the '29 Dodge set up for? Smile

Ken H.





John and i made some with 2 linoleum floor tiles with grease in between.

you mention that the 2 holes in the front crossmember are offset. i've always jacked up the front by placing the jack under those 2 holes.

now when setting the rear ride height with the jack set like that and front wheels removed the ride height would be wrong because of the off center position of the jack.
am i correct?



Fred V
'77 Royale RB 455
P'cola, Fl
Re: [GMCnet] interesting front alignment [message #100769 is a reply to message #100475] Thu, 23 September 2010 08:37 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
In 1973 when Ford started using radial tires, we had problems and on of the
fix was to flip the front tires around.
I have been informed by the local tire shop that the newer tire technology
allowethem to be rotated any way with out problems.
Radial cord set is something I have not heard in years, but worth looking
into.

On Mon, Sep 20, 2010 at 6:33 PM, Paul Leavitt <leavittpaul@yahoo.com> wrote:

>
>
> I maintain the machines that do over 400 alignments per day. The MOST
> important thing to do BEFORE you drop off a vehicle for an alignment job is
> to check your own tire pressure. Low tire pressure will cause to much CAMBER
> and just mess up everything. I watched an engineer order a repairman change
> a rearend because of too much camber. After the swap the camber was
> unchanged. Suprise!!! Low tire pressure. Used the same tires. They went and
> swapped tires and the camber changed. Correct pressure. Remember,,,I
> maintain the machines but don't work on the product. The regular alignment
> engineer was off that day.
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist



Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] interesting front alignment [message #100820 is a reply to message #100763] Thu, 23 September 2010 18:52 Go to previous messageGo to next message
gmcrv1 is currently offline  gmcrv1   United States
Messages: 839
Registered: August 2007
Location: Memphis
Karma: -1
Senior Member
At the cable facility I suported for Western Electric, we would put 4 mil
plastic sheets under the rims of 10,000lb cable reels and the 100lb women
would spin the reels so they could splice the 3,600 pair cables.

Could something like that be used for turntables? I had a pair of Snap-On
alignment stands and tables. I lent the tables to a racing buddy of mine
who eventually passed away. I think he took the tables with him - as no one
could find them...

Tom Eckert N2VWN
73 Glacier
Oakland, TN

On Thu, Sep 23, 2010 at 7:55 AM, fred veenschoten <fredntoni@cox.net> wrote:

>
>
> Ken Henderson wrote on Tue, 21 September 2010 18:17
> > As I mentioned before, I haven't decided how I'm going to measure the
> +-20*
> > steering rotations. How do you do that (without swivel platforms)?
> >
> > Oh yeah, which lane is the '29 Dodge set up for? :)
> >
> > Ken H.
>
> John and i made some with 2 linoleum floor tiles with grease in between.
>
> you mention that the 2 holes in the front crossmember are offset. i've
> always jacked up the front by placing the jack under those 2 holes.
>
> now when setting the rear ride height with the jack set like that and front
> wheels removed the ride height would be wrong because of the off center
> position of the jack.
> am i correct?
>
>
> --
> Fred V
> '77 Royale RB 455
> P'cola, Fl
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Re: [GMCnet] interesting front alignment [message #100822 is a reply to message #100820] Thu, 23 September 2010 20:18 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
Messages: 3046
Registered: November 2005
Karma: 2
Senior Member

Tom,
Yes, heavy plastic is mentioned in some of the write-ups -- along with linoleum squares, steel plates, all with grease.


Dennis Sexton
73 GMC
Germantown, TN
USA



-----Original Message-----
From: Tom Eckert <gmcrv1@gmail.com>
To: gmclist@temp.gmcnet.org
Sent: Thu, Sep 23, 2010 6:52 pm
Subject: Re: [GMCnet] interesting front alignment


At the cable facility I suported for Western Electric, we would put 4 mil
lastic sheets under the rims of 10,000lb cable reels and the 100lb women
ould spin the reels so they could splice the 3,600 pair cables.
Could something like that be used for turntables? I had a pair of Snap-On
lignment stands and tables. I lent the tables to a racing buddy of mine
ho eventually passed away. I think he took the tables with him - as no one
ould find them...
Tom Eckert N2VWN
3 Glacier
akland, TN
On Thu, Sep 23, 2010 at 7:55 AM, fred veenschoten <fredntoni@cox.net> wrote:
>

Ken Henderson wrote on Tue, 21 September 2010 18:17
> As I mentioned before, I haven't decided how I'm going to measure the
+-20*
> steering rotations. How do you do that (without swivel platforms)?
>
> Oh yeah, which lane is the '29 Dodge set up for? :)
>
> Ken H.

John and i made some with 2 linoleum floor tiles with grease in between.

you mention that the 2 holes in the front crossmember are offset. i've
always jacked up the front by placing the jack under those 2 holes.

now when setting the rear ride height with the jack set like that and front
wheels removed the ride height would be wrong because of the off center
position of the jack.
am i correct?


--
Fred V
'77 Royale RB 455
P'cola, Fl
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

______________________________________________
MCnet mailing list
ist Information and Subscription Options:
ttp://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist



Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: [GMCnet] interesting front alignment [message #100830 is a reply to message #100763] Thu, 23 September 2010 21:41 Go to previous message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
That's right -- the assumption most of us have had, that the center of the
#2 crossmember was half way between the two bottom holes is incorrect.
Measure the distance to them from the cutouts at the ends of the
crossmember. Not far off, but enough to deserve consideration. It should
have been obvious from the very beginning, since all of us know the engine's
offset to the right, right? :-)

Ken H.


On Thu, Sep 23, 2010 at 8:55 AM, fred veenschoten <fredntoni@cox.net> wrote:

> ...you mention that the 2 holes in the front crossmember are offset. i've
> always jacked up the front by placing the jack under those 2 holes.
>
> now when setting the rear ride height with the jack set like that and front
> wheels removed the ride height would be wrong because of the off center
> position of the jack.
> am i correct?
>
>
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist



Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Previous Topic: Rear Brake Adjustment
Next Topic: A look at the Competition ca 1973
Goto Forum:
  


Current Time: Fri Nov 15 19:15:39 CST 2024

Total time taken to generate the page: 0.01819 seconds