2022 Silverado 2500HD Duramax Transmission Temp High with Normal Driving, Not Towing

D Fowers · November 2, 2022

Update: I just got off of the phone with the dealership and they have received the valve body for my truck. I will be dropping it off in the morning to have it installed. I will update once I have had a chance to drive it and see if fixes the transmission temperature issue. This has been a long frustrating 4 months, let's hope this is the fix!

D Fowers · November 4, 2022

UPDATE.....I picked up my truck yesterday afternoon after having the transmission valve body replaced and it looks like that did the trick. The transmission temp got as high as 142 yesterday and even went down to 138 at one point. I am excited, I feel like I finally have the new truck I ordered after having it for 4 months. I hope this is the fix for the others on here having similar issues. If anything changes I will post another update.

Jim 2022 · November 4, 2022

2 hours ago, D Fowers said:

UPDATE.....I picked up my truck yesterday afternoon after having the transmission valve body replaced and it looks like that did the trick. The transmission temp got as high as 142 yesterday and even went down to 138 at one point. I am excited, I feel like I finally have the new truck I ordered after having it for 4 months. I hope this is the fix for the others on here having similar issues. If anything changes I will post another update.

That's awesome news! I'm still waiting on the valve body to arrive and hope to have my truck back soon! Thanks again for posting and sharing.

Jim 2022 · November 22, 2022

Update...I just called again to check the status of the valve body part that has been on back order for my truck. My truck has been parked at the GMC dealership service department since 10/13/2022. I finally have an ETA date of 11/30/2022 for the part to arrive. Hopefully the part will arrive at the end of the month and that it will resolve the issue! I'll provide another update the first part of December.

Jim 2022 · December 13, 2022

Update...the dealership received the replacement valve body for my new 2022 GMC Sierra 2500HD Denali. They got it installed and I picked up my truck on 12/1/22 and have not had any more problems so far. The highest temperature that I've seen the transmission fluid reach so far is around 155 degrees. I have yet to tow anything but the temperature was reaching around 256 degrees before and without towing anything. Yay!

Diesel2023 · August 12, 2023

Hello. I have the same exact issue going on with my 2022 GMC Sierra 2500HD AT4. My truck has about 5200 miles. I towed for the very first time last week and my transmission overheated on me. A message popped up on the dash saying transmission to hot idle engine. Took the truck in the shop 3 days ago. They said my transmission valve body needs to be replaced. Thanks to this forum I was able to communicate with the shop mechanic and get it properly diagnosed without having to go back and forth. I did In fact call GM and asked about a loaner/rental truck. And they told me that I would have to pay for it up front and then get reimbursed for it after repairs are done. First of all that’s very unfair, if my truck is in the shop for 2-3 months bc of a back ordered part. You shouldn’t expect your customers to pay for a rental vehicle for 3 months and then wait to get reimbursed. It gets expensive. And it’s GM responsibility to make it right bc it’s a faulty part on their vehicle they manufactured. So I’m kinda pissed off about that part and will continue to push for them to cover the cost upfront or I’ll just have to go straight to the BBB.

Jim 2022 · August 14, 2023

On 8/12/2023 at 11:08 AM, Diesel2023 said:

Hello. I have the same exact issue going on with my 2022 GMC Sierra 2500HD AT4. My truck has about 5200 miles. I towed for the very first time last week and my transmission overheated on me. A message popped up on the dash saying transmission to hot idle engine. Took the truck in the shop 3 days ago. They said my transmission valve body needs to be replaced. Thanks to this forum I was able to communicate with the shop mechanic and get it properly diagnosed without having to go back and forth. I did In fact call GM and asked about a loaner/rental truck. And they told me that I would have to pay for it up front and then get reimbursed for it after repairs are done. First of all that’s very unfair, if my truck is in the shop for 2-3 months bc of a back ordered part. You shouldn’t expect your customers to pay for a rental vehicle for 3 months and then wait to get reimbursed. It gets expensive. And it’s GM responsibility to make it right bc it’s a faulty part on their vehicle they manufactured. So I’m kinda pissed off about that part and will continue to push for them to cover the cost upfront or I’ll just have to go straight to the BBB.

I agree, this forum was so helpful in identifying the issue, even though the mechanics wouldn’t take my word for it in the beginning and took several days to finally replicate the problem. Kudos to my dealership though for providing me with a rental car throughout the whole ordeal and never having to pay a dime upfront. Best of luck!

Frankyg25 · March 11

On 7/20/2022 at 11:11 AM, D Fowers said:

Picked up my brand new truck on 7/9/22 with 8 miles on it. Drove it that day, normal conservative driving on pretty flat roads. Outside temperature that day was around 100 degrees. At about 30 miles on the odometer, the clutch fan kicks in which was pretty loud. Engine temp was at 210, no problem. At that time I didn't know how to pull up the transmission temp so I don't know what it was. I drove straight home and when backing into the garage I hear the dash dinging and I see "Transmission Hot Idle Engine" warning which I found out will appear if the Trans temp reaches 260 for 5 seconds or more. Took it in, they couldn't replicate the issue or find any problems. The next weekend I had about 120 mile trip (not towing) with mostly flat driving and the trans temp reached 232. My brother in his 2020 Silverado 2500HD Duramax was double towing (5th wheel and Razor) up large hills got up to 160-175 degrees. I'm frustrated and hesitant to tow anything with the way my truck is acting. The service department acts puzzled and not sure what to do. It is actually there right now being looked at. Wondered if anyone else has experienced these kind of issues or has any ideas.

My truck is doing the same thing it’s a 2021 Silverado v8 5.3 any information would help me out too !! TIA