2022 GMC At4 2500 service 4wd

[JO JO]

SERVICE 4 WD AND PARKING BRAKE IS AUTOMATICALLY COMING ON 

 

This is exactly what my 2020 2500 HD is doing.  

 

So what works to fix this issue?

[nocturnalmotors]

3 hours ago, JO JO said:

SERVICE 4 WD AND PARKING BRAKE IS AUTOMATICALLY COMING ON 

 

This is exactly what my 2020 2500 HD is doing.  

 

So what works to fix this issue?

Dealer reflashed my TCCM. So far so good.

[SCBenji]

The auto function is a terrible idea IMHO.. The trucks equipped with the auto t-case are completely different than what most are used to. They have clutch packs in them like a transmission and/or a Limited slip differential. I would be willing to bet they are slipping and overheating causing the issue. Its not old school chain or gear driven tech. 

 

When working with your truck and 4wd is needed, I highly recommend putting it in 4hi or 4low and leaving that auto button alone... 

 

This is an issue in most 1/2 ton trucks that have the auto t-case. 

[GMCustomerService]

On 1/11/2023 at 11:19 AM, JO JO said:

SERVICE 4 WD AND PARKING BRAKE IS AUTOMATICALLY COMING ON 

 

This is exactly what my 2020 2500 HD is doing.  

 

So what works to fix this issue?

This is certainly not what we like to hear, JO JO.  Please know, customer satisfaction is extremely important to us. Our team would be more than happy to take a closer look into the concerns with your 2020 2500 HD. To do so, please send an email to [email protected] with ATTN: JO JO/GM Trucks in the subject line.

Please include your contact information, VIN, a brief description of your concern, and the name of your preferred dealership. We look forward to hearing from you. To learn more about GM’s Privacy Policy, please visit https://www.gm.com/privacy-statement.html. The information you provide may be monitored and recorded and is subject to the GM Privacy Statement.
 
Privacy Statement | General Motors
Your privacy is important to General Motors. This Privacy Statement addresses the personal information GM collects and how GM handles that personal information.
www.gm.com
 

[TWS-Midland]

^{I just recently bought a used 2021 AT4 with 28400 miles. After driving 400 miles and stopping for fuel, I noticed the service 4 wheel drive message come up, so I called the dealership and they told me to run by the local dealership and have them run it through there scanner. I told them I have another 400 miles to drive to get home and would take in first thing Monday morning. When I got home the parking message came up. The next morning I noticed that there was transmission oil leaking underneath the truck. Anyone have transmission oil leaking?}

[newdude]

On 1/12/2023 at 11:29 AM, SCBenji said:

The auto function is a terrible idea IMHO.. The trucks equipped with the auto t-case are completely different than what most are used to. They have clutch packs in them like a transmission and/or a Limited slip differential. I would be willing to bet they are slipping and overheating causing the issue. Its not old school chain or gear driven tech. 

 

When working with your truck and 4wd is needed, I highly recommend putting it in 4hi or 4low and leaving that auto button alone... 

 

This is an issue in most 1/2 ton trucks that have the auto t-case. 

 

 

There is still a chain drive in the case.  The clutch pack serves the purpose of auto operation.  

[Cole0127]

Mine at the dealership for the 2nd time in 6 months for the same exact reason. Dealership says without an active code nothing they can and go figure my warranty is getting ready to expire so I’m sure I will get taken to the bank once it decides to fail. They have pulled history code c119e but not wanting to do anything to make it right as always. 80k truck with zero 4wd got to love it.