While driving thru an intersection with a yield my vehicle suddenly stopped and the engine RPM climbed to around 3500 RPM. The transmission slipped between gears causing a sudden and unexpected slow down.luckily another driver was alert and had to slow down quickly to keep from hitting us as we were merging with traffic.this never happened before and came on without warning.as soon as it happened once it has been happening more often, I brought the vehicle in and the diagnosis was the "wave plates" in the transmission. The mechanic informed me that this transmission had an issue with a part that was not properly heat treated and caused it to fail.I called the GM dealer and they would not warranty because we were just outside the 100,000 mile warranty period. They also stated that they knew there have been many issues with this vehicle but GM has not issued any type of recall.now I need a new transmission at a cost of around 4,000 dollars. I have owned several GM vehicles in the past and gotten well over 250,000 miles with no issues at all. This could have been very serious and caused injuries if the circumstances were different and someone who panicked was involved. I feel that this should warrant a recall and force GM into looking into this further. Thank you for your time.

- Sutton, MA, USA

Initially noticed when shifting from park to another gear shifting was hard. About a week later noticed hesitation in shifting gears while driving at various rates of speed then the engine would rev once it shifted into gear. Eventually parked the car in drive then went to back out to take to dealership and it would not go into reverse. Vehicle towed to dealership where they replaced the wave plate and other parts that were contaminated. Since this incident the vehicle has not drove smoothly or shifted gears smoothly. It also gets less than 15 miles to the gallon during my daily commute now where prior to the transmission fix I would get 19-20. Vehicle hesitates and revs continually while driving and accelerating. When I returned the vehicle to the dealership stating there was still an issue I received "we could not replicate the issue" and sent on my way. After research on this site and other and reading the systemic issues others have had just like it I am concerned for my family and those around me safety if the transmission decides to stop while traveling high speed in traffic or when crossing traffic.

- Pasadena, MD, USA

The contact owns a 2009 GMC Acadia. The contact stated while driving approximately 65 mph the transmission stalled with the illumination of the warning indicator. The vehicle was towed to an independent mechanic for diagnosis. The technician stated that the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 78,000. The VIN was unavailable.

- Fort Worth , TX, USA

Transmission wave plate issue...car started "hard-shifting" from 2nd-3rd gear...once this started, in a matter of a couple of days, had trouble even shifting into gear...barely was able to drive it to dealership where they diagnosed the issue...my issue is that I have to pay $4500 for something that is a known dangerous problem with GMC Acadias across almost all model years based upon my research on the internet. This should be a recall situation. There is obviously a fault somewhere with the assembly process to be this huge of a problem. This could lead to a major accident. On 9/27, I was turning left off a main road into my subdivision. Car would not engage into gear, so was just coasting across the lane where oncoming traffic would be until it engaged maybe 3 to 4 seconds later. Had there been traffic coming, the oncoming vehicle would have slammed into me before I could have gotten across.

- Brentwood, TN, USA

My wife was driving her 09 Acadia and all of a sudden it quit shifting and the engine revved up if she went over 25 mph. She limped it to a local service station where they informed us that the reverse clutch pressure plate was broken and needed a new transmission. Even though it was within GM's 5yr 100K "powertrain warranty", they "conveniently" excluded that problem from being covered. I have seen many, many complaints regarding this issue and it is[xxx] that GM isn't owning up to it and correcting the problem on current vehicles. So, now we are out $3500 for a new transmission on a car with only 75K miles! information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6). *updated 1/15/2014

- Ballwin, MO, USA

Transmission began slipping when I was accelerating out of turns. Dealer replaced broken motor mount and reprogrammed computer and said transmission was fine. 17 days later, 3-5 reverse clutch went out and dealer had to rebuild 3-5 reverse and 4,5,6 clutch and replace torque converter because of contamination. The car still isn't driving right but dealer states they can't find anything wrong with the vehicle. This is a very common problem with '08 and '09 Acadia's and GMC is aware of the problem but isn't don't anything to prevent failure with other owners.

- San Diego, CA, USA

* transmission was slipping and revving up between gears. Delayed response and clunking sound when it is in reverse. "check engine light" also came on. Barely drove the car to the dealership for repairs. Dealership service advisor scheduled a transmission rebuild. After doing internet search, I saw countless complaints in blogs, sns, etc. There are so many people having this transmission problem. Not acceptable. GMC has powertrain warranty 5 year /100K miles. My warranty expires in four months and GM should provide extended powertrain warranty beyond 5 years based unreliable transmission design/quality. * power steering problem. Power steering is making moaning under low speed driving (in the parking lot, driving around subdivision, etc.). noise is coming from the inside steering column area. Also steering is very tight and hard. Complained to dealership multiple times. Dealership replaced the seal twice, but the problem is still there. Dealership told me that GM does not have a fix for this problem.

- Alpharetta, GA, USA

2009 GMC Acadia slt1 - 67,000 miles currently. Power steering failing at lower speeds. When purchasing the vehicle used with only 25,000M+- approx. 2 years ago, I questioned the dealership about the whining noise coming from the steering components and was told that this is normal for all acaidias and not a concern. Now the steering is failing at low speed turns. GMC service dept recommending: Steering gear housing $42.14 - 2 bolts $11 - 2 - bolts $7.59 - 6 - P/S fluid $23.10 and flush and bleed system, labor to replace steering gear housing $640.50 power steering pump $155.69 realign after steering gear repair $69.95 labor for pump $315 injectors and coils failing. In Dec 2011, I had to replace coils #2 & #3. I just replaced #6 injector on July 17, 2013 (= $685) and on July 24, 2013 (one week later) check engine light reappeared. GMC service dept recommending: 4 - ignition coils $373.30, 6 - spark plugs $42.25, labor for coils, and plugs $241.50............................................................ total parts $655.07 total labor $1197 tax $54.04 align $69.95 total: $1976.06 offering 40% customer portion pay $790.42 why is there no recall on defective steering components & coils/injectors? in the later 2012 models GM did change the power steering & fluid, so GM is aware that there is a problem with the design. The fuel delivery system is also defective and faulty coils/injectors could and have caused fires. GMC Acadia, Buick enclave & Chevrolet traverse vehicles up to early 2012 models share these above mentioned components are plagued by these two problems along with transmission (wave plate) problems. GM needs to take full responsibility for defective components and not offer discounted repairs.

- Weatherford, TX, USA

My vehicle began to "jump" when you press on the gas petal. Then it had trouble finding a gear. I took it in to the dealership and they said that they could not replicate the problem. I was then coming home from work at 5pm in traffic, going 65 miles an hour in the fast lane and the transmission failed. The car would not move forward or backwards. I was left in the middle of the road in heavy traffic where people could easily hit my car. I was able to guide the car to the side and a tow truck came and towed me into the dealership. They returned the car a week later saying that it was working as designed. I was then driving up to eureka ca and the transmission began to slip. The car would not go past 35 miles per hour. I was on a busy freeway at the time. I took it to repair and they tested it and said that transmission sensors where faulty. There was no dealership there so I drove it back to the san francisco bay area with my hazard lights on at 35 miles per hour with the transmission wining the whole time. The car was returned to me a week later saying that the transmission had been repaired. A couple of weeks later I was driving and felt the transmission slip again. I took it in to the dealership and they said that they could not replicate the problem. I told them that I was sure I was going to be back as this was the pattern of the car. The car is now in the shop after the transmission failed again on a busy street while I was driving. This issue is well documented for this car at around 60,000 but there has been no recall. Does someone need to get hurt for a recall to happen?

- Lafayette, CA, USA

First problem was the timing chains needing to be replaced at 18000 miles. After that repair was made the gas mileage was averaging 11 mpg. It was a one year old car! after that, it was a multitude of problems. Steering rack/power steering replaced and 'fixed', electric stabilitrak lights going on and off, dvd player not playing properly. All things the dealer had said they fixed (after they whispered that I should not have bought an american car.) now the transmission is acting up. Rolling down an incline when I was trying to back out of a parking spot. The dealer told me it was fine and they could not duplicate the issues I was having. I've written two letters to GM corporate to complain about the sub-standard vehicle. They were helpless and will not assist in any replacement of the car. They even told me that this would be a difficult car to trade in considering the problems I have had with it. Who is kidding who? I would never recommend this car and hate to continually put my family in it.it is unsafe. Period.

- Brightwaters, NY, USA