Alignment/drifts To Left...need Help!

jscan · July 19, 2008

I have an 08 sierra 2500 hd with about 1900k with 17" rims and bridgstone all terain tires from the factory and i have a drifting to the left problem, not a pull but a drift even in the far right lane. sometimes it will go right with the crown of the road but still favors left. the dealer swapped the front tires left to right and that did not help, i rotated back to front and with the new tire from the rear with the 1900k on them still do the same thing maybe a little worse because there was no wear on them from being on the rear for the first 1900k. the dealer put it on the alignment rack and the alignment is actually about a half degree favoring pulling to the RIGHT. so the dealer is stumped! I took it to an alignment shop and they verified that the truck should be slightly going to the right. they dont know either and said they could cheat it more to the right but that might mask the problem if there even is a problem. they said they did not want to touch it and to go back to the dealer. any tech help out there?

Zembonez · July 19, 2008

There is no giant mystery here. It's in the alignment unless you have a brake dragging. You could have a caliper (or even a rear drum) dragging and creating a slight pull. If the brakes check out... A good alignment tech can fix this by tinkering with caster / camber settings. Simply setting it up on the machine and "reading" the alignment means nothing. Vehicles are an assembly of thousands of parts and they all react a little differently to alignment settings.

EDIT: When checking brakes I've found that measuring pad thickness is a reliable way to tell if a brake is dragging or not. This is especially true on a low mileage new vehicle. If there is an obvious difference in pad wear (measurable) That brake is not releasing completely and might cause a slight pull. Sometimes this is accompanied by a pull when you brake. Try hands off braking in a flat parking lot and see if it pulls.

Good luck and don't worry. It's fixable!

pm26 · July 20, 2008

Hmmmm, 1900k (=1,900,000 miles) is a lot on an '08 truck.

The alignment setting that causes the truck to pull to one side, if adjusted improperly, is CASTER. The left and right caster are slightly different to compensate for a crown in the road. So one front wheel is slightly ahead of each other.

They need to play around with the caster settings to cancel the pull.

slimjim2525 · July 20, 2008

Hmmmm, 1900k (=1,900,000 miles) is a lot on an '08 truck.

The alignment setting that causes the truck to pull to one side, if adjusted improperly, is CASTER. The left and right caster are slightly different to compensate for a crown in the road. So one front wheel is slightly ahead of each other.

They need to play around with the caster settings to cancel the pull.

yup, this is true.

Zembonez · July 20, 2008

Hmmmm, 1900k (=1,900,000 miles) is a lot on an '08 truck.

The alignment setting that causes the truck to pull to one side, if adjusted improperly, is CASTER. The left and right caster are slightly different to compensate for a crown in the road. So one front wheel is slightly ahead of each other.

They need to play around with the caster settings to cancel the pull.

yup, this is true.

Another fact:

A vehicle can be "within specs" and pull like crazy. Adjustment within the rated range can have a big effect. Having somebody just look at it really doesn't tell you much.