2006 Z71 crew cab wheel alignment

pm26 · August 17, 2006

I took my truck in for wheel alignment today because I noticed that the right front tire was getting scrubbed on the outer edge and somewhat on the inner edge too. There was some scrubbing evident on the left front tire too, but much less than on the right one. In comparison, the rear tires were worn very evenly. The truck has only 3,300 miles and this is not normal. The tires are factory 265 Bridgestone Duellers on 17 inch rims.

When I got the alignment before and after spec printout, I noticed that the right front wheel caster specified range was 2.8 to 4.8 degrees. The actual caster, which was left uncorrected is 2.1 degrees. It was not changed during the alignment. Should I be concerned about this being out of spec? The truck does not pull or drift. The caster setting on the left front wheel is 2.5 degrees, which is within the range (2.5 to 4.5). This was not changed.

Would this cause tire feathering (scrubbing) on the edges? In my experience, it was always improper toe-in that caused this. Improper caster settings generally cause the vehicle to pull or drift. The caster setting on the right front wheel is slightly different from the left front wheel to compensate for the crown of the road.

The toe settings on the front wheels prior to alignment were:

-0.03 for the left front wheel, and 0.00 for the right front wheel. They were set to 0.05 and 0.07 degrees, respectively. Ideally you want the identical settings on both wheels, but 2 hundreds of a degree should not cause a problem.

Based on these settings, could the former toe adjustment have caused feathering on the edges of front tires? It does not seem that much of a difference.

Finally, the printout says that these are the specs for a 1500 heavy duty crew cab (6.0L) truck. My truck is a crew cab light duty 1500 Z71 with a shorter frame. Are the specs the same for both trucks, or did they screw this up?

Raymond S. · August 17, 2006

I have the same truck. Rotated tires just last week @6k miles and noticed the same thing. It is currently in the shop today getting the LF Hub assembly replaced. I may have them check the alignment while they're at it.

TEE · August 17, 2006

GM is terrible about having too much camber angle on their wheels...have someone drop it to 0

pm26 · August 17, 2006

GM is terrible about having too much camber angle on their wheels...have someone drop it to 0

<{POST_SNAPBACK}>

The camber on both front wheels is set to 0.1 degrees right now. I just rotated my tires today and will keep an eye on the front ones. If I see any funny wear in the next 1000 miles or so, it goes back for realignment. Thanks for the tip. Zero camber sounds like a good idea.

I still question why they left the caster on the right front wheel at 2.1 degrees, if the spec range is 2.8 to 4.8 degrees. Improper caster normally causes pulling or drifting, not tire edge scrubbing. Now the toe-in is positive instead of negative. But somehow I still think that improper caster can have some negative infulence on tire wear in turns at speed.

Does anybody has any experience with tire wear with negative toe-in (e.g. -0.1 degrees on both front wheels)? I like positive toe -in better, as the wheels tend to spread apart in turns, making the positive toe-in pretty much zero.

pm26 · August 17, 2006

I have the same truck. Rotated tires just last week @6k miles and noticed the same thing. It is currently in the shop today getting the LF Hub assembly replaced. I may have them check the alignment while they're at it.

<{POST_SNAPBACK}>

Why are they replacing the left front hub? Did you have vibration problems or unusual noise while driving? Is this something that I should be concerned about? Is this diagnosis based only on uneven tire wear? Is there a known problem with these hubs?

I had a hub replaced on a Mazda 626 car within waranty because the hub was improperly assembled and the wheel holes did not line up with the studs on the hub and wheel had to be forced on (if you can believe that). I personally tried bolting a wheel on that hub and it was true!

pm26 · August 19, 2006

Here is an update on my alignment:

I went back to the dealership and talked to the service manager and asked why was the caster setting left out of spec on my truck. He went to investigate this, and came back with another alignment spec sheet printed from the machine. This one has somewhat different parameters, and it is supposedly correct. The alignment specs for a 2006 C/K Silverado, Sierra W/17" tires, regular, extended, or crew cab:

caster, left front: + 2.30 deg +/- 1.00

caster, right front: + 2.55 deg +/- 1.00

cross caster (L-R): -0.15 deg +/-0.75

camber (L and R): +0.25 deg +/-0.60

cross camber (L-R): 0.00 deg +/-0.60

toe(L and R): +0.10 deg +/-0.20

steering wheel angle: -1.0 deg +/-3.5

According to these new (presumably correct) alignment specs, my caster settings are within specifications. What I find odd though is that my left front wheel is actually leading the right front wheel, and the truck does not pull or drift. It should be the other way around: the right wheel should have slightly higher positive caster than the left wheel? What is the explanation here?

I have a question for the GM tech: Are these the right alignment specs for a 2006 K 1500 crew cab? Also, what toe settings do you recommend to minimize the front tire edge wear ( feathering or scrubbing)? The nominal setting is specified as +0.1 degrees. This means the front wheels are pointing slighly inward in the front. The toe on my truck now is set to +0.05 and + 0.07 degrees. Does negative toe setting (even within permissible range) have a bigger effect on uneven front tire wear?

pm26 · August 19, 2006

Hello? GM tech? Anybody home? I need some help here!

MrHughes919 · August 24, 2006

ITS THE TIRES....heres this document...take it with you to the dealership and enjoy the free tires!!!!

Document ID# 1840958

2006 Chevrolet Chevy K Silverado - 4WD

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Subject: Bridgestone Dueler Product Information Update - keywords alignment blister front pressure rear tire vibration wear wheel #PIT3562B - (06/19/2006)

Models: 2004-2006 Chevrolet Avalanche, Suburban, Tahoe

2004-2007 Chevrolet Silverado Classic

2004-2007 GMC Sierra Classic

2004-2006 GMC Yukon, Yukon XL, Yukon Denali

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This PI has been updated to provide fix information. Please discard PIT3562A.

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The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Bridgestone tire information update.

Recommendation/Instructions:

Customer concerns have been received relative to vibration, flat spotting, wear, etc. on trucks equipped with P265/70 R17 Bridgestone Dueler A/T tires with TPC spec # 2328. Engineering has released a new tire to help minimize these concerns.

If the below maintenance items have been followed and the tire issues described above still persist, replace the tires with a Bridgestone Dueler A/T RHS with a TPC # of 2345. These tires should be available in the near future (1-2 months). Check with your local Bridgestone tire dealer for availability. Please do not call TAC for tire availability issues.

• Tire Rotations (every 5,000 - 8,000 miles (8,000 - 13,000 km) per Section 5 of the Owners Manual)

• Tire Pressure (Adjusted to the door sticker)

• Proper Wheel Alignment per SI

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

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Document ID# 1840958

2006 Chevrolet Chevy K Silverado - 4WD