Automatic Transmission Control Module problems of the 2008 GMC Acadia

Check engine light came on for the tcm. Car has had issues shifting (very rough shifting) and the manual shift option does not work. Was told the tcm had to be replaced. Attempt was made to replace it with a refurbished tcm but that couldn't be programmed to the car. Was then told I would have to buy a brand new one, which is very expensive, and that there was no guarantee that would fix the problem. Car can not be driven over 20mph without risking burning up the transmission. Car also jerks forward very hard when trying to gently accelerate.

I've come to find out my car is throwing a code for the tcm being stuck turns out this is an extremely common issue as well as the wave plate for this model GMC should be held responsible being this is their design flaw and seems to be an issue across the board for almost all Acadias of these years.

The contact owns a 2008 GMC Acadia. While driving 40-45 mph, the engine would not switch gears. The contact pulled over to the side of the road, turned off and restarted the engine, and was able to drive the vehicle to the contact's residence. The contact experienced the same failure 18 months ago. The vehicle was taken to todd wenzel Buick GMC (614 n state rd, davison, mi 48423) where it was diagnosed that a new transmission control module was needed. The manufacturer was contacted at 1-800-462-8782 and did not assist. There were no recalls associated with the vehicle. The failure mileage was 124,000.

Purchased vehicle from dealer with 72000 miles with 4yr/48000 mile warranty. Warranty ran out this summer, mileage is now 133000 miles. Problem has been intermittent since early last year, but mechanics were not able to help because problems were not 'presenting' as the check engine light would go on and off at different times (just as the recalled service air bag light did!). In December 2015, the check engine began staying on all the time and the gears did not shift correctly. The tcm is messed up, which is a very common problem with all Acadias, apparently. We had a very scary issue on xmas eve with the gears downshifting while we were on the highway and it wouldn't let me go over 20mph! we took it to first dealership over an hour away and the guy came out with a handheld computer, put in on our car, said it is our tcm and $3800 to fix it. He never put anything in the computer, so we didn't have an official diagnosis. We spoke with gm and they said to get the diagnosis and they would see about helping us to cover it. So, we got the diagnosis today, it is the tcm and no help. They said it is out of warranty, gm won't cover it, it is up to the dealer to cover it, etc. We have been told so many different stories about why they won't cover it, just that they won't. Our VIN number is literally 6000 off of the recall list! it is a common problem and should have been a national recall! does anyone know of a class action lawsuit? I would love to be a part of one.

My Acadia (which I just bought in March) began shifting harshly between the 3rd and 5th gears and my check engine light came on. The next day I took it to an auto repair shop where I had the codes read and was told I had a problem with the 35r waveplate and the transmission control module. I was told I would have to pay $600 just to have my transmission taken apart to diagnose the extent of the damage. I was told that a drum came apart causing "extensive damage" and that I would either need a complete transmission rebuild for $3600 or a brand new transmission for $4000. This car has less than 100,000 miles on it (although I know that is high for the year, a brand new transmission for a fairly new car is extreme). I was told by the mechanic that this is extremely common for the 08 Acadias and it was not uncommon for this particular car to go through several transmissions before reaching the 100,000 mile mark. This is a joke. GMC needs to recall the car and pay the costs of the many owners who are having to pay thousands of dollars to repair a part that should not have been put in the car in the first place!.