07 Obs Brake Issues

Sonoma · January 22, 2008

Hi everyone

Wife's truck - 07 Silvy "Classic" OBS

Brakes issues from 7000 miles til now 24000 miles

Pulsating is driving us crazy!!

1st trip to dealer - cut the rotors

2nd trip to dealer - cut the rotors

3rd trip to dealer - cut the rotors on the vehicle THEN replaced them because they were too thin and cut the rear drums

4th trip to dealer - cut the rear drums.

Did not replace the pads or shoes at any time which they said they were not obligated to do under the warranty.

Called GM and said you have to go thru the dealer.

We have now spoken with the General Manager who is speaking with the Service Manager. "We'll get back to you."

Now waiting.

I want new rotors, drums, pads and shoes with a brake flush thrown in.

Any thoughts?

pm26 · January 22, 2008

I suspect that they are using cheap rotors on these trucks. The solution appears to be an upgrade to better rotors. The only thing you could do in the mean time is avoiding hard braking by cautious driving and ensuring all lug nuts are hand torqued to specifications.

Note: They should have replaced the rotors first time. By turning them, they removed the metal and made them thinner, and even more prove to warpage. They should have replaced the pads and brake shoes as well. Not replacing them and reusing them with new rotors/drums is dumb.

I have an '06 crew cab and one of my rotors is grooved without any reason. No adverse effect on brake performance, but I have only 7k on the truck. I think I'll replace the OEM rotors and pads with better aftermarket products when the time comes. I did not bother to take the truck to a dealer under warranty because of the rotor grooving. I know they would just turn the rotors, making the problem worse. They are treating the symptoms, not the disease as I see. The solution is better rotors, drums and associated pads/brake shoes.

Lincoln30 · January 22, 2008

I went thru a few rounds of warranty replacement of warped rotors on my 99 GMT800. I finally got sick of taking it to the dealer every few thousand and purchased a Praise Dyno Stage II rotors/pads (mine is 4wheel disk and I think 99 rotors were smaller then 06). This was not cheap at $900 but more then 100K miles later I'm still running the same rotors with no problems and just last week got new pads and resurfaced the rotors.

jrrod2004 · January 22, 2008

I went thru a few rounds of warranty replacement of warped rotors on my 99 GMT800. I finally got sick of taking it to the dealer every few thousand and purchased a Praise Dyno Stage II rotors/pads (mine is 4wheel disk and I think 99 rotors were smaller then 06). This was not cheap at $900 but more then 100K miles later I'm still running the same rotors with no problems and just last week got new pads and resurfaced the rotors.

Here is GM's Answer to the grooving:

Document ID# 2003792

2007 Chevrolet Silverado Classic - 2WD

Subject:Scored Appearance On Front Brake Rotors - keywords disc groove pad #PIC4049B - (08/15/2007)

Models:2007-2008 Cadillac Escalade, Escalade ESV, Escalade EXT

2007-2008 Chevrolet Avalanche, Silverado, Suburban, Tahoe

2005-2007 Chevrolet Silverado Classic with RPO JF3 or JF7

2005-2007 GMC Sierra Classic with RPO JF3 or JF7

2007-2008 GMC Sierra, Yukon, Yukon XL, Yukon Denali, Yukon Denali XL

1500 Models

This PI is being superseded to update modelyears. Please discard PIT4049A.

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

Condition/Concern:

Some owners may comment on a scored appearance of the front brake rotors. This scoring could be caused by the make up of the front brake lining. The brake lining formula has ingredients to clean rust off the rotor braking surface. This cleaning feature of the rotor braking surface may have a side effect of scoring.

Recommendation/Instructions:

This scored appearance is normal as long as no other symptoms are experienced such as pulsation, roughness, noise, and the scoring does not exceed the specification in SI Doc ID 1476240.

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

Document ID# 2003792

2007 Chevrolet Silverado Classic - 2WD

Notice how it says : This scored appearance is normal as long as no other symptoms are experienced such as pulsation, roughness, noise, and the scoring does not exceed the specification in SI Doc ID 1476240.

how convenient, best solution is mentioned above, replace the entire rotor/pad with something better aftermarket. I get the feeling that GM is putting the 'standard' parts in our trucks and leaving us to foot the bill for any GOOD parts, but that is my .02 cents.

pm26 · January 22, 2008

I went thru a few rounds of warranty replacement of warped rotors on my 99 GMT800. I finally got sick of taking it to the dealer every few thousand and purchased a Praise Dyno Stage II rotors/pads (mine is 4wheel disk and I think 99 rotors were smaller then 06). This was not cheap at $900 but more then 100K miles later I'm still running the same rotors with no problems and just last week got new pads and resurfaced the rotors.

Here is GM's Answer to the grooving:

Document ID# 2003792

2007 Chevrolet Silverado Classic - 2WD

Subject:Scored Appearance On Front Brake Rotors - keywords disc groove pad #PIC4049B - (08/15/2007)

Models:2007-2008 Cadillac Escalade, Escalade ESV, Escalade EXT

2007-2008 Chevrolet Avalanche, Silverado, Suburban, Tahoe

2005-2007 Chevrolet Silverado Classic with RPO JF3 or JF7

2005-2007 GMC Sierra Classic with RPO JF3 or JF7

2007-2008 GMC Sierra, Yukon, Yukon XL, Yukon Denali, Yukon Denali XL

1500 Models

This PI is being superseded to update modelyears. Please discard PIT4049A.

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

Condition/Concern:

Some owners may comment on a scored appearance of the front brake rotors. This scoring could be caused by the make up of the front brake lining. The brake lining formula has ingredients to clean rust off the rotor braking surface. This cleaning feature of the rotor braking surface may have a side effect of scoring.

Recommendation/Instructions:

This scored appearance is normal as long as no other symptoms are experienced such as pulsation, roughness, noise, and the scoring does not exceed the specification in SI Doc ID 1476240.

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

Document ID# 2003792

2007 Chevrolet Silverado Classic - 2WD

Notice how it says : This scored appearance is normal as long as no other symptoms are experienced such as pulsation, roughness, noise, and the scoring does not exceed the specification in SI Doc ID 1476240.

how convenient, best solution is mentioned above, replace the entire rotor/pad with something better aftermarket. I get the feeling that GM is putting the 'standard' parts in our trucks and leaving us to foot the bill for any GOOD parts, but that is my .02 cents.

Which means they would not do anything about my rotors anyway. This bulletin serves to give GM a way out without doing anything. I wonder about "rust removing" pad formulation causing grooving. And how dos it do that? Do the pads have steel spikes cast into them? And why is this happening only on one of my rotors? Only the right side pads have this feature?

jrrod2004 · January 22, 2008

your guess is as good as mine...........

Zembonez · January 22, 2008

The grooving issue is a separate one. If they turned all of your rotors and drums with no change in the pulsation, it is very possible that you have an out of round tire, a bent or warped wheel, etc. I hope these items were checked by the dealer? There are other items that can cause a pulsation in the brakes. A lot of times these issues will also be accompanied by a vibration at certain speeds but this isn't always the case.. .