GM Waiting to Fix Transmission on my 1 Day old AT4

Colossus · February 24, 2020

1 hour ago, Pinnacle said:

yes they shared 9 speed tech aswell, they go deep Ford and GM been done many times

Fiat Chrysler uses a 9-speed on a number of their SUVs and such.. any relation?

Pinnacle · February 24, 2020

11 minutes ago, Colossus said:

Fiat Chrysler uses a 9-speed on a number of their SUVs and such.. any relation?

None, thats German ZF. Whole can of worms that one is too.

19gmcsierraat4 · February 24, 2020

9 hours ago, wacnstac said:

I have the 10 spd on a LT TB. It has 1000 miles and I have it in for a leak. I think it was leaking since day 1. I had the dealer undercoat the truck and you can see where the undercoating didn't stick to a frame member under the trans because it had fluid on it.

Haven't been able to find much online about these 10 speeds leaking. Where was your leaking and how bad?

Mine wasn't leaking to bad actually. Maybe a dime size of oil overnight. It was leaking right in front where it connects to the engine. Ill see if i can upload some pics once I get home from work.

wacnstac · February 25, 2020

On 2/24/2020 at 2:36 AM, 19gmcsierraat4 said:

Mine wasn't leaking to bad actually. Maybe a dime size of oil overnight. It was leaking right in front where it connects to the engine. Ill see if i can upload some pics once I get home from work.

Well mine is the rear output shaft seal. Has been in the shop since Friday morning and will be there at least until Monday.

wacnstac · February 25, 2020

On 2/23/2020 at 1:24 AM, 19gmcsierraat4 said:

Yup! They couldn't fix the leak. They replaced seals and it continued leaking. Replaced with a brand new one.

What was the build date on your truck?

Shane Lozynski · May 1, 2020

On 10/28/2018 at 9:39 PM, pronstar said:

It’s a weekend, doesn’t seem unreasonable for them to wait for the GM rep to approve it on Monday...?

Sent from my iPhone using Tapatalk Pro

It wasn’t unreasonable when they took his 60K to 70K

mcoaker · May 27, 2020

What was the outcome of your issue with the 1 day old 10 speed? Last week I had a similar issue with my 2020 2500 HD Duramax 10 speed. 3 weeks and 1800 miles in, the truck would not move. Had to have it towed to the nearest dealer.

Had just launched my boat after a short 2 mile pull to the ramp. Unhooked from the trailer at the house and pulled forward about 20 ft. When I shifted to reverse, the truck rolled forward slightly and then would not move in reverse. Shifted back to drive and it rolled forward. Back to reverse and nothing. Eased down on the accelerator and it was as if the truck was in neutral. Back to drive and after a clunk, the check engine light came on. I was able to roll forward enough to get out of the street with throttle but it would barely move. Like the truck was stuck in 10th gear or something was slipping. Parked it in the neighbors yard and towed it the next morning.
Dealership is saying everything worked fine when it arrived. They supposedly backed it off the wrecker normally and it’s been driving fine. Check engine light is off now and the only codes are “low voltage” and “loss of communication”. Any ideas or similar experiences? Very frustrated and concerned. Grateful for any input

JohnTz · May 27, 2020

11 hours ago, mcoaker said:

What was the outcome of your issue with the 1 day old 10 speed? Last week I had a similar issue with my 2020 2500 HD Duramax 10 speed. 3 weeks and 1800 miles in, the truck would not move. Had to have it towed to the nearest dealer.

Had just launched my boat after a short 2 mile pull to the ramp. Unhooked from the trailer at the house and pulled forward about 20 ft. When I shifted to reverse, the truck rolled forward slightly and then would not move in reverse. Shifted back to drive and it rolled forward. Back to reverse and nothing. Eased down on the accelerator and it was as if the truck was in neutral. Back to drive and after a clunk, the check engine light came on. I was able to roll forward enough to get out of the street with throttle but it would barely move. Like the truck was stuck in 10th gear or something was slipping. Parked it in the neighbors yard and towed it the next morning.
Dealership is saying everything worked fine when it arrived. They supposedly backed it off the wrecker normally and it’s been driving fine. Check engine light is off now and the only codes are “low voltage” and “loss of communication”. Any ideas or similar experiences? Very frustrated and concerned. Grateful for any input

My brother and I bought 2020 AT4s at the same time about a month ago. Great trucks. He had the exact same thing happen to him on Monday. The problem was that Both his kid left there laptops on and charging in his car for two days. They sucked down the battery enough that when under the load of the starter the voltage dropped low enough to screw up the startup procedure of many systems in the truck. He got a ton of low voltage codes and a check engine light and the trans was all screwed up and wouldn’t shift out of his garage. Put it in a charger overnight and everything was back to normal the next day. These new trucks are rolling computers. Any voltage issues will screw them up big time.

mcoaker · May 27, 2020

Man thanks for the feedback. That's just odd because the truck had only been turned off for 2 hours max. And it cranked right up without dragging or anything. But maybe that was it. Just a fluke that hopefully won't happen again

kpanza · May 27, 2020

On 2/22/2020 at 10:24 PM, 19gmcsierraat4 said:

Yup! They couldn't fix the leak. They replaced seals and it continued leaking. Replaced with a brand new one.

Interesting...my 275 mile 10 speed leaked from day 1 also...they replaced the torque converter seal, still leaked (was in shop 2 weeks that time). Is now on Day 58 IN THE SHOP, they are waiting on a new trans pump...but my dealer rep has requested a new transmission, so far no answers. Really disappointing. Have now made 4 payments, and got to drive the truck a grand total of 3 weeks between repairs. GM has approved a buyback or replacement, but now there are hardly any trucks to choose from.

ryangv26 · September 13, 2020

I’m having a similar situation. I bought a 2020 At4 in August while it was still in transit to the dealership. When I went to pick it up two weeks later it had trouble shifting into reverse when they were getting it out of the wash bay. Service dept called gm who said to have the whole transmission replaced. Fast forward a month and I still don’t have my truck. Got an update the replacement trans has been built but not shipped yet. Having mixed feelings now about taking delivery of it after it’s fixed. Should I get out and start from scratch?

Colossus · September 13, 2020

how would you get out?

ryangv26 · September 13, 2020

5 hours ago, Colossus said:

how would you get out?

Back out of the sale, get money back etc

RODMAN70 · September 13, 2020

Hi all! I too have a 2020 TB w/the 10 spd & 5.3. At 3800 miles I left the house & the truck made a hard, truck jolting bang into the next gear. Stopped to pick up some dinner & NO reverse! Good thing I could drive straight outta there. Checked this site & saw the low battery issue might be the culprit for trans, so I charged it overnight. Next day same issue, hard banging shift, idiot lights on dash, stuck in gear. Take off from a stop sign was like riding the clutch in a stick car. I had to shut it off, restart it, take off, bang, drive to dealer. They ordered a new valve body & it's been ok since. I don't drive it much. lost faith in the truck, gm wont buy it back. I've been buying GM trucks for the past 12 years, this is # 7. Very disappointed & don't know what I'll buy next.