GMC AT4 hard shifting

[Cola Blanca]

I know I could have gotten it fixed under warranty but in my mind if they weren't competent enough to find the leak then they weren't going to pull and replace the transmission correctly so I dumped her

[Dirt Napper]

I drove it today with no signs or symptoms. I took it easy and had no abrupt stops. It seems like it only downshifts hard when you make a quick stop. Feels like it’s skipping gears. No leaky transmission after 200 miles. Kinda missing the Ford already. Haha.

[Dirt Napper]

I should be able to provide an update soon. Truck is going through the service department tomorrow. Hoping it’s just a faulty TCM. But should be resolved in the end, regardless. Under warranty and bought the extended because I was scared of the little diesel. Guess I should’ve been more concerned with the under-engineered transmission.

[Big Lee]

I should be able to provide an update soon. Truck is going through the service department tomorrow. Hoping it’s just a faulty TCM. But should be resolved in the end, regardless. Under warranty and bought the extended because I was scared of the little diesel. Guess I should’ve been more concerned with the under-engineered transmission.

Over engineered

[JBJTX81]

Without out riding with you to feel what's going on its hard to know for sure. But it sounds like the torque converter clutch. Maybe it needs a reflash? I know after I tuned a few diesels in the past and the tune also remapped trans. It really had the TCC working overtime to protect the transmission from the additional power. It was only slightly bothersome though.

[papaw]

Keep driving as you normally would still learning shift adapts. Towing will also cause a change in shifts as well as a different driver.

[bbqfan5909]

Hate to break the news, but ford and gm use the same 10 speed.

I drove it today with no signs or symptoms. I took it easy and had no abrupt stops. It seems like it only downshifts hard when you make a quick stop. Feels like it’s skipping gears. No leaky transmission after 200 miles. Kinda missing the Ford already. Haha.

[Bucknaked]

Hate to break the news, but ford and gm use the same 10 speed.

Joint venture but 2 different transmissions!

[Big Lee]

Joint venture but 2 different transmissions!

All internals are literally identical.

[bowhntrmatt]

I'm betting they find an issue. I have a '22 Tahoe with what I would assume is the same transmission and I really like the way it operates and puts power down, and rarely ever feel a shift at all.

Now the 6 speed in my 2018, different story. garbage.

[meangreen]

Having the same issues with my 2022 f250 7.3 gas. Shifts like crap!

[meangreen]

45,000 miles, had it reflashed, still the same. About to dump it

[Dirt Napper]

I guess having an update “soon” was a little too optimistic. After today, they will have had it for 3 days without looking at it. That brings me to my next question. Should I expect service to be expedited on a brand new vehicle that’s less than a week old? Or is service just service, regardless of the situation? Guess it’s no more important than the 10 year old truck that needs an alternator or coil packs. I’m just losing my patience because I expected more out a brand new product.

[Headhunter]

I had the same problem you described on my 2018 HD. Would downshift extremely hard “loud pop” when coming to a stop. Did it in the early stages like maybe 3 times. I would pull over and shut truck off and restart and it would be gone. Shop didn’t find anything other maybe transmission learning. Drove it for 120k miles before I got the newer HD AT4. But I had zero issues with my 2018 outside of maybe those 3 hard downshifts.

[Big Lee]

I guess having an update “soon” was a little too optimistic. After today, they will have had it for 3 days without looking at it. That brings me to my next question. Should I expect service to be expedited on a brand new vehicle that’s less than a week old? Or is service just service, regardless of the situation? Guess it’s no more important than the 10 year old truck that needs an alternator or coil packs. I’m just losing my patience because I expected more out a brand new product.

When they look at it. Has nothing to do with the manufacturer.