EvansBlue

minnuplander, could you take a picture of the rear suspension and post it? I know it may be kinda hard with a 5.5" ground clearance, but maybe we can confirm that you do in fact have a trailing arm suspension.

fscoles

You mentioned your Uplander still has the (original) Goodyear Integrity tires...our '08 also came with Integrity's. Ours started having serious tire wear problems well before 30K miles when we had purchased it used (scalloping, cupping, etc.) but the area's best technician using Hunter laser-aligning equipment reported it was tire problems, not a vehicle problem; and to switch tire brands, as they've experienced other Integrity wear problems. Several months after his diagnosis, I absolutely had to switch tires, because both Integrities on the front had thrown belts and were seriously out-of-round, making scraping noises, a dangerous situation. I'd think it could be difficult to impossible for one to diagnose possible vehicle suspension or shock problems if the tires are no good. Our current Firestone FR710's are doing well, and there are other good brands available.

Papa Bear

Shawn... can you shed a a little light on this tire wear thread ??

I don't believe that the rear end of an Uplander has alignment adjustments... have you seen Goodyear problems in your travels ??

shawnvw

OK, everybody is right here. There are 2 different types of rear suspension. Independant Rear Suspension(IRS) with leading a trailing control arms and the whole bit.
This type is found in AWD models. The also have whats called a Twist Axle, which is basically a peice of steel going from side to side, this type is found in FWD models.

As far as rear Alignment is concerned, if its a FWD, make sure nothing is bent. If its AWD, the toe and camber are adjustable
But in all cases, toe and camber are adjustable in the front. If the caster is out of align, something is bent or loose.

IRS



Twist Axle

shawnvw

Tire Diagnosis - Irregular or Premature Wear




Tire Wear




<MAP name=386773.map><TABLE><TBODY><TR><TH align=left></TH></TR><TR><TD align=middle>(1)</TD><TD align=left>Under-Inflation, Hard Cornering, Lack of Regular Rotation</TD></TR><TR><TD align=middle>(2)</TD><TD align=left>Incorrect Wheel Alignment, Hard Cornering, Lack of Regular Rotation</TD></TR><TR><TD align=middle>(3)</TD><TD align=left>Incorrect Wheel Alignment</TD></TR><TR><TD align=middle>(4)</TD><TD align=left>Over-Inflation, Heavy Acceleration, Lack of Regular Rotation</TD></TR><TR><TD align=middle>(5)</TD><TD align=left>Normal Wear to the Wear Indicator</TD></TR></TBODY></TABLE>
Inspection Procedure

1. Inspect the front tire wear.
2. Inspect the rear tire wear.
3. Rotate the tires if any of the following conditions exist:
   <TABLE border=0><TBODY><TR><TD vAlign=top>• </TD><TD vAlign=top>The amount of time or mileage since the last tire rotation matches the maintenance schedule.</TD></TR></TBODY></TABLE>
   
   <TABLE border=0><TBODY><TR><TD vAlign=top>• </TD><TD vAlign=top>The outer tread blocks are worn more than the middle tread blocks (1).</TD></TR></TBODY></TABLE>
   <TABLE border=0><TBODY><TR><TD vAlign=top>• </TD><TD vAlign=top>The outer tread blocks are worn more than the inner tread blocks (2).</TD></TR></TBODY></TABLE>
   
   <TABLE border=0><TBODY><TR><TD vAlign=top>• </TD><TD vAlign=top>The middle tread blocks are worn more than the outer tread blocks (4).</TD></TR></TBODY></TABLE>
4. Measure the wheel alignment if any of the following conditions exist:
   <TABLE border=0><TBODY><TR><TD vAlign=top>• </TD><TD vAlign=top>The tread blocks have feathered edges (3).</TD></TR></TBODY></TABLE>
   

   <TABLE border=0><TBODY><TR><TD vAlign=top>• </TD><TD vAlign=top>The outer tread blocks are worn more than the inner tread blocks (2).</TD></TR></TBODY></TABLE>
   
   <TABLE border=0><TBODY><TR><TD vAlign=top>• </TD><TD vAlign=top>The inner tread blocks are worn more than the outer tread blocks (2).</TD></TR></TBODY></TABLE>
5. Inspect the struts or the shock absorbers if the tire tread exhibits a cupped appearance (3).

</MAP>

minnuplander

SOrry for taking so long to get back. Lets start over. Front wheel drive, Striaght rear axle, no independant rear suspenion, tires are wearing on the inside, Had it to village chev and put on the rack they said allignment was within the tolerances(front and back)

capucine

My uplander also has developped a small cupping wear on the inside of the rear tires. The front tires are perfect. My van has only 10,000 kilometers. I am planning to rotate only the rear tires to start the wearing on the reverse.You are right that it has a solid axle on the rear. it is called a twist beam.

sa16bnav

The rear tires have a -1 camber. The shocks that came on my 2006 Uplander are called Soft Ride. They don't hold the tires on the road very well and if you have mid price tires(El Cheapos) they will chop out. I replaced my shocks with a premium grade and the choping has not gotten worse..

Papa Bear

-1 camber will wear the tires, rotation is very important on the van. I used to do 10k rotations and I'm now doing 5k.

Read my post here https://chevroletforum.com/forum/upl...y-34884/page1/ and a lot of good input by a tire engineer (CapriRacer) in my thread at BITOG here Rotated my tires today... - Bob Is The Oil Guy (The post began in 2009 but gets updated in June 2010. The post tells the whole story of my rear axle experience and CapriRacer says the closer to ZERO camber the better, -1 in at the "edge" of causing rapid tire wear and cupping/noise problem) . I installed Munroe Sensa-Trac rear shocks and the van was like a different (BETTER) vehicle.

So, YES, the rear axle can be aligned AND MANY OF OUR VANS NEED IT. Get your camber closer to ZERO front and rear and your tires will thank you with a longer, quieter life.

sa16bnav

The tires have a factory set -1 degree camber(in at the top) and can not be changed. Go to a premium shock. The factory shocks are junk. I changed my shocks and the wear has stopped. (Chopping out). The -1 degree was there to improve handling according to my GM mechanic plus factory cheap tires added to the problem. GM needs to stop reinventing the wheel. My 2006 Uplander has had 3 itermediate stearing shafts, one fuel gauge sender and one hub bearing. All in 71,000. This is my last GM product....Hal