I have taken the truck to the dealer twice for hard shifting and they replaced the trans fluid and flashed the computer. It seemed to fix the problem for about 6 months then it would gradually start doing the same things, slipping and hard shifting, especially when coming to a stop or slowing down. After the second time at the dealer, they told me that’s how the transmission was designed to shift. After that I have just dealt with the problem because of the trouble of getting an appointment and the time of them checking the truck out.
Now I am out of the powertrain warranty and the transmission is really bad, slipping, hard shifting and losing power. It’s also making a whining noise at 20-30 mph. No help from the dealer now because I’m out of the warranty, even though it was a preexisting problem. So now I am spending $4700 on a new transmission. Very dissatisfied that a transmission only lasted 70,000 miles. This truck has been a daily driver, never abused, and always maintained by the dealer. I see why GM changed their warranty from 100,000 mile to a 60,000. I have been a Chevy/GM guy since I was 16. I really hate to have to drive non American truck, but GM is leaving me no choice. You would expect a more reliable vehicle after spending over $50,000 on a vehicle. Hopefully I can get a few more miles out of this truck before I trade it in on a Tundra.
GMC knows this is a major problem, yet chooses to nothing about it. My truck has had this problem for a long time. It is the 2nd time the transmission has been flushed but I don't figure it will help the issue.
This is the fourth time we have had this vehicle in for repair. It lurches forward and in reverse, shifts hard between 1st and 2nd and makes the rear end clink when it does this. All GMC seems to want to do is re-train the transmission, but maybe they should re-train their engineers. Afraid that one of these times it is going to lurch and cause an accident or injury.
Bought truck used with about 12K miles on it. Started noticing immediately that transmission has a hard time figuring out what to do when you want to do it. Hard shifts, sever hesitation on cold mornings, terrible whining sound towards end of each gear. Truck just cannot put without me thinking the whining sound, through gears, is not good. Towards the end of a gear, if you let off gas and press slightly back down, the terrible whining/grinding sound emits. Have not taken it anywhere yet but i need to. The whining is getting worse and more obnoxious. This has really turned me off of GMC's and will most likely not purchase another.
I have now owned the truck for over a year. Bought in October 2017. I started noticing it shifting oddly after about a month of having it. Was working to much to take it in right away. My first visit to the dealer was 1/30/2018. They said it just needed a computer update and that will fix it. They did the update. I went and picked it up and was pulling out of the dealership it still was doing it. What a waste of my time...
The last straw was about 4 weeks ago when I was turning right at a stop light. Made the turn and a normal rate of acceleration and the transmission seemed to not engage and then jerked into gear throwing my head back into the head rest tweaking my neck that hurt for a week. This also happened about 3 weeks prior to that experience. Wow not fun. The truck at low speeds just cannot make up its mind on which gear to go into. Just slows and then surges forward.
GM knows there are issues with the transmissions and that they have no fix for it. Took it in 3x now. January 2018, July 2018 and October 2018 to 2 different dealerships. They just say we know it does it but GM has no fix for the problem. Both service managers said that GM will not do anything to fix the problem of the slipping and surging. So as a consumer I will never own another GM product. Stuck for now with my neck hurting and a truck that is not shifting properly...
Transmission problems started 5 months after I bought the truck new. Hard downshifts, clunking and slipping out of drive at stop signs on hills. Dealer said it's part of the break in period and will go away (we'll see based on the number of complaints and forums about it out there).
I purchased a 2017 GMC Sierra Denali from George Carr Buick Cadillac GMC, Inc. located in Vicksburg Mississippi on December 29th 2017.
When I test drove the truck I instantly noticed a vibration on the freeway. The salesman Herb Caldwell assured me that it was just a simple flat spot in the tires from sitting in the lot. Sounded reasonable to me. He said, "Don't worry. It would be 100% fixed!" The tires were replaced and this has yet to correct the problem, during the last visit I was told it was the transmission and my vehicle was at the dealership another 5 days and once I picked the vehicle up I was informed that the tires were out of balance, shortly after leaving the service department I called back and spoke with John Toney the service manager and informed him that this vibration was not only back but now the transmission and/or rear differential are making a loud clucking sound. This occurs while driving at low speeds and when coming to stops, example while pulling away from stop sign, loud clunk and the vehicle surges forward.
1. Repair vehicle vibration at below and above 40 miles per hour
2. Fix vehicle vibration at idle
3. Resolve the engine bucks and missing issue
4. Resolve the jerking and surging motion of the vehicle
5. Replace Tire with factory brand tires and not no names as previously done
6. Repair the loud clucking transmission banging and slamming noises heard in the transmission and rear differential
A D V E R T I S E M E N T S
I have taken the truck to the dealer twice for hard shifting and they replaced the trans fluid and flashed the computer. It seemed to fix the problem for about 6 months then it would gradually start doing the same things, slipping and hard shifting, especially when coming to a stop or slowing down. After the second time at the dealer, they told me that’s how the transmission was designed to shift. After that I have just dealt with the problem because of the trouble of getting an appointment and the time of them checking the truck out.
Now I am out of the powertrain warranty and the transmission is really bad, slipping, hard shifting and losing power. It’s also making a whining noise at 20-30 mph. No help from the dealer now because I’m out of the warranty, even though it was a preexisting problem. So now I am spending $4700 on a new transmission. Very dissatisfied that a transmission only lasted 70,000 miles. This truck has been a daily driver, never abused, and always maintained by the dealer. I see why GM changed their warranty from 100,000 mile to a 60,000. I have been a Chevy/GM guy since I was 16. I really hate to have to drive non American truck, but GM is leaving me no choice. You would expect a more reliable vehicle after spending over $50,000 on a vehicle. Hopefully I can get a few more miles out of this truck before I trade it in on a Tundra.
- Brian F., Bella Vista, US