8 speed tranny hard shift

I’m sorry you are having problems with your transmission–that is very frustrating. I had a 2014 GMC Sierra with a 6-speed that I was not fond of at all. It was a beautiful truck, but it clanked and slammed into gear and you could tell the transmission was programmed to get into top gear as quickly as possible and stay there at all costs. My problems got much worse after about 10k miles–my coworkers went from admiring the truck to asking me what was wrong with it when they rode with me. I kept complaining about it at every maintenance visit. A GM tech once told me, “Be glad you don’t have the 8-speed because it is worse!” I test drove a 2019 Denali with an 8-speed on a cold night and didn’t make it off the dealer’s lot before it slammed so hard that my wife and I thought I had run over something. If you look at gm-trucks.com, you will see plenty of complaints about the 8-speed and a few people who say it is great. If you look at the news section of carcomplaints.com, you will see that GM is seeking to dismiss a class action suit against the 8-speed by claiming it is not a warranty issue because it is a design defect, not a manufacturing defect. How’s that for customer relations?

If you have a good dealer, try to get them to do the double-flush and refill with the new style transmission fluid. Some people say this helps, but may not necessarily fix the problem. Sadly, the 8-speed transmission seems to just have issues for a lot of people.

After test driving a new Nissan Titan (too expensive and depreciates terribly) and a Toyota Tundra (ancient design and a major gas drinker), I bought a 2020 GMC Sierra SLT with the 10-speed transmission about a year ago. After 13k miles, it is still very difficult to even tell when the transmission is shifting and DFM is a massive improvement over AFM. At the very least, this truck will last me until the new Tundra comes out (supposedly 2022) or a viable electric pickup truck hits the market. I am hoping the new Tundra will get competitive fuel economy and I will be able to leave GM’s design defects behind.

Good luck!

GM’s transmission problems have not gone away with new models either. I purchased my 2021 Canyon AT in November 2020. Right out of the box I noticed the trans having a strange noise while still in park. Also noticed the hard or harsh shifting from 1-2 and some very hard downshifting at times. All this problems are intermittent and have not shown up during my two visits to the dealer’s service department. Last visit was a couple weeks ago (around 1/6/2021), when I picked up my truck I was given a GM bulletin which basically states, yeah we understand there are problems but they do not effect “anything” therefore we are not going to do anything. What the heck?? Kind of like saying, Yeah, we took your money and to bad your so dumb to know better. Does anyone know if 2021 models are or can be included in this Class Action Suite?