Huge win for car owners! All TSBs to be made public. The Center for Auto Safety just made the NHTSA (US Government) make public the full text of all TSBs from now on. They are the same organization that has petitioned the NHTSA & filed lawsuits to protect car owners over exploding gas tanks & other major safety issues. Whenever you drive in your car, you are safer thanks in part to a lot of work over the years by this small but very effective consumer advocacy group.

Please take a moment & say thank you by donating $5 or whatever you can to the Center for Auto Safety.

Print this page


hardly worth mentioning
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
66,983 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2006 Chevrolet Avalanche transmission problems

transmission problem

Find something helpful? Spread the word.
Get notified about new defects, investigations, recalls & lawsuits for the 2006 Chevrolet Avalanche:

Unsubscribe any time. We don't sell/share your email.

2006 Chevrolet Avalanche Owner Comments

problem #4

Oct 272010


  • 90,000 miles


The contact owns a 2006 Chevrolet Avalanche. The contact stated that the transmission failed while he was driving approximately 60 mph. He was unable to move forward although the rpms increased. There were no warning lights prior to the failure. The vehicle was taken to a transmission center where the transmission was replaced. The contact called the manufacturer and filed a complaint about the failure. The current and failure mileages were approximately 90,000.

- New Orleans, LA, USA

problem #3

May 212010


  • 79,100 miles
2006 Chevrolet Avalanche 1500 4WD in 2wd hi, driving at 55 mph with transmission in D, engine revved freely as if transmission in neutral. Coasted to a stop onto shoulder, shifted into park, released foot brake, vehicle began to roll forward (downhill), apparently because transfer case shifted into neutral. Ses indicator not on. Turned off engine. No codes (had code reader in glove box). Turned engine on, shifted transmission into D and felt transmission engage (apparently, transfer case had engaged from neutral). Accelerated gradually and drove down highway for 1/4 mile and when accelerator pedal was released, transfer case shifted into neutral, again, engine revving freely with transmission still in D. coasted to a stop on shoulder, pressed 4WD hi and felt transfer case engage, pressed 2wd hi and felt transfer case disengage but now in 2wd hi instead of neutral. Accelerated gradually and drove down highway and when accelerator pedal was released, transfer case shifted into neutral, again, engine revving freely with transmission still in D. coasted to a stop on shoulder, and repeated above sequence on transfer case to shift into 2wd hi. Shifted transmission into 3, accelerated gradually and drove down highway, transfer case remained in 2wd hi. Slowed down to a stop on shoulder, turned off engine, restarted engine and shifted transmission into D, accelerated gradually and drove down highway and when accelerator pedal was released, transfer case shifted into neutral once again. After coasting to a stop, repeated sequence to engage transfer case into 2wd hi, shifted transmission into 3 and drove vehicle to mechanic. Still diagnosing issue.

- Yonkers, NY, USA

problem #2

Feb 102006


  • 89,596 miles
Driving home last night, I lost 3rd and 4th gears in my transmission under normal acceleration. I have an '06 Chevrolet Avalanche Z71 with less than 89,600 miles on it. I have never towed anything except for a uhaul trailer once for about 250 miles. I was on the highway when this happened, traveling 50-55 mph when it occurred. I was able to coast to a stop on the shoulder of the highway without further incident, however I was almost rearended by following traffic the moment it happened because of the sudden decrease of speed without warning. The transmission gave no warning before it broke. I still had 1st and 2nd gears as well as reverse. I have spoken with a mechanic and he estimates repair costs to be around $3000. I have checked several forums for people who have experienced similar problems and have found that this is a "common" problem happening to Avalanche that are 2-6 years old and having as few as 14,000 miles on them. My truck is out of warranty, but this is a pervasive problem that has existed since 2002 according to other Avalanche owners. The forums I found the information on are;,, and This is more than an isolated incident, having happened to many people who own Avalanche's as evidenced on the forums. This defect is known by GM as evidenced by there own technical service bulletin number "08-07-30-027 June 08    A/T - no movement in drive or 3rd gear". it is a flawed design or flawed parts are being used. GM should recall all affected trucks with this particular transmission and take corrective action before someone is fatally injured due to a failure on a congested highway. An investigative look at GM's repair records to see how many trucks have been in for repairs, that have experienced the same or similar failures, would probably warrant a federal investigation into the safety of this product, and whether GM should be compelled to institute a recall.

- Tool, TX, USA

problem #1

Sep 222006

Avalanche 8-cyl

  • Automatic transmission
  • 9,235 miles
The contact owns a 2006 Chevrolet Avalanche 1500. The air bag light illuminated on the instrument panel. The dealer repaired the failure, but it recurred the following year. The failure was repaired a second time. The contact stated that the vehicle has been taken to the dealer repeatedly to have the air bag failure repaired. He also stated that the front seats were making strange noises. He took the vehicle to the dealer twice to have the seats repaired. The transmission also needed to be repaired. The contact stated that the air bag failure was a safety hazard. The failure mileage was 9,235 and current mileage was 45,000. Updated 10/03/08 the transmission would not move in forward gear. The dealer found the sprag broke and the clutches were burnt. The front door speaker made a buzzing noise. The dealer stated it was an internal failure. Updated 10/06/08.

- Antioch, CA, USA

Not what you are looking for?