Hey, everyone... long time lurker, but just joined up today, so this is my first post. I've gleaned a lot of good info from here, but having exhausted the search function, I wanted to ask about something I've not been able to find info about here.
I've been experiencing a squeak from the brake pedal in my 2011 Colorado 2wd (Reg. cab, 3.7, 4L60E) which sounds like the squeak or groan of wet rubber shoe soles on a tile floor. It is most apparent when sitting in traffic and letting up a bit on the brake pedal to inch forward, and you can feel a vibration from the squeak through your shoe. The truck has 82,000 miles on it and has had no brake mods except for regular flushes (about every other year) with Valvoline Synthetic DOT4. This is NOT a brake pad or shoe noise at all, and the brakes work fine, This is definitely something in the brake pedal/booster/master cylinder area.
After doing some research elsewhere, I found on some Acadia, Trailblazer, etc. forums a similar complaint on those cars. The following TSB was mentioned, which advises the use of a new, update DOT 3 fluid with improved "lubricity."
#08-05-22-002D: Squeak Noise on Brake Apply (Remove Brake Fluid from Master Cylinder and Refill) - (Jul 21, 2010)
Subject:
Squeak Noise on Brake Apply (Remove Brake Fluid from Master Cylinder and Refill)
Models:
2004-2007 Buick Rainier
2008 Buick Enclave
2004-2010 Chevrolet Colorado, TrailBlazer, TrailBlazer EXT, TrailBlazer SS
2008-2009 Chevrolet Malibu
2004-2010 GMC Canyon, Envoy, Envoy XL, Envoy XUV
2007-2008 GMC Acadia
2008-2009 Pontiac G6
2007-2008 Saturn OUTLOOK
2008-2009 Saturn AURA
2005-2009 Saab 9-7X
--------------------------------------------------------------------------------
This bulletin is being revised to update model years. Please discard Corporate Bulletin Number 08-05-22-002C (Section 05 - Brakes).
--------------------------------------------------------------------------------
Condition
Some customers may comment on a squeak noise when the brake pedal is applied or when released. This noise is normally heard when the brake pedal is slowly applied with the engine on or off, but can occur when the brake pedal is released. The noise may be isolated to the master cylinder area.
Correction
To correct this concern, remove as much of the old brake fluid from the master cylinder as possible and refill with a new DOT 3 brake fluid, P/N 88862806 (in Canada, use P/N 88862807). Start the vehicle and fully cycle the brake pedal until the noise diminishes to allow the new fluid to enter the system.
The part number for the above mentioned fluid has been superceded by GM #19299818, the item shown here:
Brake Fluid Dot 3 88862806 19299818
So, just yesterday I did a thorough system flush with the new DOT 3, but after a full day of driving I have found that it did not alleviate the noise. It's still VERY much there. I've read about dealerships going so far as to replace vacuum boosters and master cylinders along with using this new fluid to deal with the problem.
So, my question is, has anyone here had this same issue and actually found the definitive cause and/or solution?
I've been experiencing a squeak from the brake pedal in my 2011 Colorado 2wd (Reg. cab, 3.7, 4L60E) which sounds like the squeak or groan of wet rubber shoe soles on a tile floor. It is most apparent when sitting in traffic and letting up a bit on the brake pedal to inch forward, and you can feel a vibration from the squeak through your shoe. The truck has 82,000 miles on it and has had no brake mods except for regular flushes (about every other year) with Valvoline Synthetic DOT4. This is NOT a brake pad or shoe noise at all, and the brakes work fine, This is definitely something in the brake pedal/booster/master cylinder area.
After doing some research elsewhere, I found on some Acadia, Trailblazer, etc. forums a similar complaint on those cars. The following TSB was mentioned, which advises the use of a new, update DOT 3 fluid with improved "lubricity."
#08-05-22-002D: Squeak Noise on Brake Apply (Remove Brake Fluid from Master Cylinder and Refill) - (Jul 21, 2010)
Subject:
Squeak Noise on Brake Apply (Remove Brake Fluid from Master Cylinder and Refill)
Models:
2004-2007 Buick Rainier
2008 Buick Enclave
2004-2010 Chevrolet Colorado, TrailBlazer, TrailBlazer EXT, TrailBlazer SS
2008-2009 Chevrolet Malibu
2004-2010 GMC Canyon, Envoy, Envoy XL, Envoy XUV
2007-2008 GMC Acadia
2008-2009 Pontiac G6
2007-2008 Saturn OUTLOOK
2008-2009 Saturn AURA
2005-2009 Saab 9-7X
--------------------------------------------------------------------------------
This bulletin is being revised to update model years. Please discard Corporate Bulletin Number 08-05-22-002C (Section 05 - Brakes).
--------------------------------------------------------------------------------
Condition
Some customers may comment on a squeak noise when the brake pedal is applied or when released. This noise is normally heard when the brake pedal is slowly applied with the engine on or off, but can occur when the brake pedal is released. The noise may be isolated to the master cylinder area.
Correction
To correct this concern, remove as much of the old brake fluid from the master cylinder as possible and refill with a new DOT 3 brake fluid, P/N 88862806 (in Canada, use P/N 88862807). Start the vehicle and fully cycle the brake pedal until the noise diminishes to allow the new fluid to enter the system.
The part number for the above mentioned fluid has been superceded by GM #19299818, the item shown here:
Brake Fluid Dot 3 88862806 19299818
So, just yesterday I did a thorough system flush with the new DOT 3, but after a full day of driving I have found that it did not alleviate the noise. It's still VERY much there. I've read about dealerships going so far as to replace vacuum boosters and master cylinders along with using this new fluid to deal with the problem.
So, my question is, has anyone here had this same issue and actually found the definitive cause and/or solution?
