Which parts fail
Components named in complaints (service brakes, ABS, rotors and pads, parking brake).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2006 GMC Sierra owners, lightly cleaned up (personal details are redacted by NHTSA).
There is no warning the pedal goes to the floor and you don't stop. I had a 5th wheel trailer hooked to my 2006 GMC 2500 ext. Cab long bed Sierra p/u with 62,459 miles on it. I was able to stop it with the trailer brakes and a scratch on my front bumper from a tractor trailer that was in front of me. I have owned over 200 cars + trucks since I started driving. I do all my one work on them and I never had a brake line fail, I will be 70 this year. It is ridiculous for an 8 year old truck to have rusted brake lines to fail. The worst part of this is that nobody notified the public that this was a problem when they GMC knows about this problem. I found a garage that fixed the two front lines. So we could get home. …
Total brake failure while in motion. Corroded brake line ruptured causing immediate loss of all fluid. Had this happened 5 minutes earlier, I would have been on a four lane highway in bumper to bumper christmas traffic. At 70 years old I can only imagine how catastrophic an accident my reflexes would have generated. The fluid sprayed on the hot engine creating a cloud of smoke. I was afraid the truck was on fire. The fluid cooked off the engine as smoke and again luckily there was no fire. Now after extensive repairs, I am very nervous behind the wheel of this vehicle. This very dangerous situation with corrosion should be addressed as blogs on the internet indicate this dangerous issue has been ongoing for quite awhile. I have attached the invoice of the repairs required. …
Brake pedal went to floor almost causing an accident before the vehicle came to a stop. Before the service light came on. The service light did come eventually at which time we checked the master cylinder which was extremely low so we filled it thinking that was the problem. The next day we noticed brake fluid dripping and after checking realized that at least one of the brake lines were were rusted through in several places and all of the other lines are terribly rusted and probably on the verge of leaking also. This is a truck that we usually pull our camper with. Luckily we were not pulling it at the time this occurred.
2006 Sierra denali with just over 75,000 miles. With 1/2 block warning and only traveling at a speed of 20mph, I was unable to come to a complete stop. The brake pedal was all of the way to the floor when I ran into a van in the intersection. I felt very little resistance from the pedal and the ABS definitely did not go off. There was no snow or ice on the road surface. However after towing the vehicle to the local dealership, I was told nothing was wrong with the truck. Two independent third parties have suggested this could be a master cylinder issue even though GMC gave it a clean bill of health.
Was coming to a stop light and brake pedal went all the way to floor. Had to step on several times to get stopped. The factory electrical wire in factory loom in factory clamp hooked to brake line wore a hole through brake line to right front wheel. Wore through directly under the master cylinder. Luckily I was not going at high speed or this could have been a fatal incident!!!!!!!!! This is something that come from factory and needs to be addressed.
Drove from baltimore, md to cleveland, oh. Parked, the next day attempted to drive and brake pedal went to floor. Brake line on drivers side toward the rear had rusted out, had to have truck towed and brake line replaced. In dec. 2014, one year later, truck was parked for 4 days in drive, went to drive brake pedal to floor again, had to have towed, 4 lines replaced.
I went to put on my brakes, I first started to stop then my brake pedal went all the way to the floor. I hit a vehicle in front of me. The collision shop that I had it repaired at said the brake lines were rusted. After further investigation I read a lot of complaints about this same defect in Chevy and GMC trucks.
I was approaching the stoplight fletcher drive and lee highway at approximately 25 MPH heading east on lee highway around 1600 edt in warrenton, va. There were four (4) cars waiting to turn left onto fletcher drive in front of me. The car in front of me came to a sudden stop. I applied the brake with approximately 2 car lengths in front of me. The brakes started to grab but then the brake pedal went all the way to the floorboard. I pumped the brakes and my truck continued to roll and then hit mr. [redacted] vehicle at approximately 5-7 MPH. I was unable to come to a complete stop until making contact with [redacted] car. I asked if he was OK or hurt and he replied yes, I am OK. Why didn't you stop?? I explained that I tried. I then suggested that both of us pull into the fauquier bank parking lot and exchange insurance information. …
I bought a 2006 Sierra denali with 65000 miles on the truck in May of 2013. I lost my brakes and almost rearended a man pulling into his driveway. I also had my 3 kids and my fiance in the truck with me. I took my truck to robertsons GMC in wareham,ma and they told me my brake lines were completely rotted as well as my frame. I also had a extended warranty which did not cover it because it was a pre-existing problem. I just don't understand how GM can get away with all of these frame corrosion and brake line corrosion problems without having to fix the problems with there trucks. I have researched alot on these problems and it seems like no one is holding GM responsible and making them fix the corrosion problem.I think they should have to fix the problem like Toyota did when they had frame problems so that they can stop producing vehicles that dont last 10 years without rotting away.
Brakes failed while coming to a stop in light traffic. Braking action reduced to approx 10 to 20 percent of normal. Driver felt a "pop" and the brake pedal went to the floor, followed by a 'service brake system' warning message. A large puddle of fluid formed under the truck when parked and a quick look under the truck showed lots of fluid from the front of the bed to the rear of the truck. Further investigation showed heavy corrosion on all rigid brake lines. All brakes lines will be replaced. The failed line powered the rear brakes. This truck is only eight (8) years old. This could have been lots worse if the brakes failed one week earlier when I was pulling a camper through the tennessee mountains.
Brake complaints in other Sierra years
Frequently asked questions
How common are brake problems on the 2006 GMC Sierra?
NHTSA has 29 complaints about the brakes of the 2006 GMC Sierra, 50% of the model year's 58 complaints. The component named most often is antilock/traction control/electronic limited slip › wheel speed sensor/tone ring (1 mentions).
Is there a recall for 2006 GMC Sierra brake problems?
No. NHTSA lists no brakes recall for the 2006 GMC Sierra, though it has 4 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2006 GMC Sierra brake problems start?
Half of the complaints with a recorded mileage happened before about 50,000 miles, and 25% before 25,000 miles.
Is it dangerous?
Owners linked 4 crashes, 0 fires and 0 injuries to brakes problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.