At 80K I put my truck in reverse and heard a clunk sound and immediately it wouldn't shift gears anymore. I went and had the transmission rebuilt which lasted roughly 10K more. Now, the truck won't shift yet again and the filter was changed and the rear output seal. Currently, when I drive since its my only vehicle, one minute it will shift fine but after I turn the engine off and on again, it will not shift from first and the again, check engine light is on!

- Mexia, TX, USA

Driving down county rd stopped at stop sign. Started to take off it started slipping then quit pulling completly.puet it in all drives 1,2,3, & D nothing happened cut engine off put it in drive it started out like nothing happened for short distance then same thing again.

- New Hope, AL, USA

While cruising on rt 101 at 65 mph, vehicle automatically downshifted into second gear for no reason. In response, I was forced to decelerate to 35 mph. Tried explicitly placing vehicle in third instead of "D" for drive, but, the drive train was unresponsive. Shortly thereafter, a "hot transmission" message appeared on dash and I pulled over and checked fluids. Fluids looked good. Drove vehicle home in second gear without issue. Upon investigation, I discovered that my Avalanche was built with a widely recognized design flaw and undersized transmission. Various sources suggested I file complaint this address: Https://www-ODI.NHTSA.dot.gov/vehiclecomplaint/index.xhtml.

- Bedford, NH, USA

The transmission began to shift hard. The answer from the dealer was need new transmission for $4500. Stated that the fluid sensor housing was cracked and the entire transmission needed replacement. Seemed a bit ridiculous for a two year old vehicle that towed nothing.

- Sunderland, MD, USA

Right after the warranty expired the transmission went and I had to rebuild it. At the shop the techs told me it was due to cooling, and they installed a small cooler because they said the cooling was not sufficient.

- Miami, FL, USA

At approx 47000 mi traveling at 65mph a heavy thud in the engine compartment that sounded like the whole engine block had dropped out, was able to coast off road to a vacant lot. Transmission toast with damage to ring and pinion gears, never towed anything, city driving to work and home mostly.(47K) miles. Really? 3500$ repair. Next speedometer failure at about 53K miles, im either going 0mph or 120mph. Also have lost alot of backlighting on my dashboard instrumentation along with cd player. Seems the cd player cannot eject a non existent cd, just makes clicking noise and says check disc. Now at 59K miles im experiencing the popping front end sound when turning sharply in reverse, possibly suspension or A-arm related have not looked into yet.

- Port Hueneme, CA, USA

Service 4wheel drive message appears. I have had this problem repaired numerous times. No codes are listed in the onboard computer. Technicians cannot identify the failing component. They replace parts until the message goes away. The vehicle shifts into 4 wheel drive without warning. This has happened to me numerous times. This happens during high humidity or rainy conditions. Numerous tsb have been issued. One common cause is wiring harness connector that is prone to fail due to moisture. Chevy has not issued a safety recall.

- Malabar, FL, USA

While driving on a 1200 mile trip, the message "service 4WD" appeared and my 2wd yellow indicator light went out. I called onstar and they performed a system diag. Could not pull any codes, so they connected me with GM. The customer service person at GM told me to reset the warning light and if it came on again to take the vehicle to a Chevy dealership. The next day the light came on again and I took it to a dealership. They wanted $990 to fix the problem. I did not have that kind of money while on my trip. They also would not verify if the vehicle was safe to take on a 1200 mile trip back home. Today (3 days later, and after I drove another 1200 miles back home), the service 4WD light is back on and now a red light is showing in the neutral position of the transfer case. I looked in the owners manual how to get the truck out of the neutral position in the transfer case and performed these actions. Not sure what will happen tomorrow with the truck. In my opinion, this should have been an open recall as I have noticed many other Avalanche owners with the same problem. My confidence is shaken now with my GM truck.

- Vero Beach, FL, USA

Vehicle transmission slipped out of gear and slammed into what I assumed park in the middle of traffic in the middle of rush hour. Thank god nobody got hurt because had there been a vehicle ridding close to be they would have ran straight into me! this is clearly an safety issue that could've cause someones' life had I've been gooing at top speeds. Somebody needs to do something about this!

- Vienna, VA, USA

On 12/22/12 @ 5pm- shortly after entering onto the freeway, I started losing power. I didn't get higher than 50 mph before the RPM started increasing & my speed started decreasing. I got off the freeway, at the first exit, approximately 2mins after the beginning of the loss of power. Found a mechanic that was just closing his shop & asked him to give a quick check too see if I could continue my drive home, 32mins away. The mechanic checked under the hood & under the bottom & guesstimated the problem to be the flywheel. The mechanic also recommended no driving til repaired. I got my Avalanche towed home that first night. I towed it to my local auto repair shop on 12/24/12, to get a full diagnostic. I was advised by my local mechanic that my 2005 Avalanche w/ 96319 mis, needs a new transmission. My local mechanic advised it may still be under warranty due to mileage, but I have since found out the warranty is 5yr/100000mi. GM is aware of premature transmission failure on the Avalanche, but is not fixing it for the consumer. Something needs to be done to protect the consumer!

- Fort Worth, TX, USA

Purchased May 31, 2005. 39 mileage. $43,000. 8 months later the transmission started jerking. We took it to the dealer 6+ times and they said they couldn't find anything. Now at 75,000 miles it won't drive in D it has to be in 3, 2, 1 to drive. I have read 100's of complaint about transmissions in 2000-2010 models. GM needs to take care of their customer transmission problem or design a better transmission.

- Town Creek, AL, USA

Clunk when going into drive, also shifts hard when driving down the road.

- Greenville, PA, USA

On January 8th 2012, while pulling out of the church lot we heard a clunk noise. The "transmission hot" display came on. We made it home at a slower rate of speed and eventually the light went out. I called GM customer service when I got home. They didn't have any suggestions, but just asked if I was towing something at the time and other questions to which the answer was no. I took my Avalanche to the dealer the next day to get it checked. On the 9th, the service manager told me that 2nd and 4th gears were out. He said they would have to tear into it to find out if it could be repaired. I asked how much that was going to be and he said around $580. I let them tear into it starting on the 10th. Didn't hear anything on the 10th or 11th but on the 12th, the service manager said that the transmission was "pretty well cooked" and it would need replaced with a remanufactured transmission for $3200. He said the remanufactured one would come with a 3yr/100,000 mile warranty. I called back GM customer service back and left a message for them to call me. Based on everything I've read on the internet, it appears that this transmission is well known for failing and I don't believe a 2005 Avalanche with only 88,000 miles on should have failed. I've use my vehicle for mostly going to and from work and on long trips. Hopefully, GM will accept responsibility for their failed defective equipment and provide me with a remanufactured transmission. I understand that this transmission is really not a "truck" transmission but is also used in some of GM's other sedans which weigh twice as less and are not used for the same types of things a truck is meant for. It's no wonder it failed. For other posts about Avalanche transmission failures, go here ==> townhall-talk.edmunds.com/direct/view/.F0F8066/0.

- Oklahoma City, OK, USA

Went to pull out of a parking lot, gave it a little gas and nothing. Engine idled up but it would not move. Went down through the gears but still would not move. Had to put it in reverse and back into a parking space and called a tow truck. $2900 dollars later the transmission was replaced with genuine GM rebuilt transmission.

- Dubois, PA, USA

Traveling home from work on the interstate at regulated speed (65mph). As I started to accelerate to maintain speed gingo up a hill, the message "transmission hot" came on the in-dash display and engine began revving as if not in gear. I could not accelerate and had to turn on flashers and merge to safety lane on right. I continued to slow down until I could engage the transmission again at around 30 mph in 3rd gear. As soon as I started to accelerate past 35-40 mph, the transmission slipped again and would not engage any gear. This happened all the way home so what should have been a 20 minute drive turned into an hour. I couldn't get above 35-45 mph without this happening each time which made navigating the hills of northern va in the rain not very fun for me nor the hundreds of frustrated drivers behind and beside me. As I pulled into the driveway and parked, I could notice a 'burnt and sour" smell...most likely transmission fluid. I didn't see any leaks or drips but the engine was extremely hot as was transmission and transfer case. This has been happening off and on for a few months now but in very limited occasions and never for more than 10-20 seconds so I haven't contacted a service station but will definitely do so this weekend as I am unable to leave work during the week for this issue.

- Woodbridge, VA, USA

2005 Chevrolet Avalanche headlight was loose and fell out while washing the vehicle. When driving the drive train makes a clanking noise. ** answer required*** after a thunderstorm, the next morning, the consumer found that water had saturated in the tailgate area.

- Peoria, IL, USA