Baker 5

Totally pisses me off that you spend big dollars on this truck and the details are crap. I have a 2020 AT4 Carbon Pro and have the same issue. CHEAP, CHEAP, CHEAP! Has anyone had success wrapping these?

When they got into my transmission, they noted "burnt fluid and metal shavings / chips" were found. Apparently not the first time GMC has seen this as they approved the replacement as soon as the Service Manager sent in the request. Have your guys dig a little deeper.

I took the fuel sample provided by the dealership to a 3rd party testing facility (QUINN Cat).

40K

Had an issue where my truck was making a horrible grinding noise from under the cab. Pulled over and had codes P0700 and P281B. I had filled up with diesel fuel about 50 miles of freeway driving earlier. Had the truck towed to my dealer and they said there was gas contamination. My first question is, can you drive a diesel truck 50 miles with contaminated fuel? Saw no black smoke, no performance issue with freeway driving. The grinding occurred 50 miles after fill-up while taking the exit off the freeway. Dealer then told me that the grinding and the transmission issues were not connected. I am positive I did not fuel with gas and confirmed that with the station as they had video of me utilizing the green nozzle and hose. No other reports of issues with the station. Secondly, is there any way a contaminated fuel situation would cause the transmission issues? The dealer did find fluid burnt and "lots of metal shavings on the transmission pan". The dealer went through the protocol of draining and cleaning the fuel issue per document # 5207114. They said that did the trick and there are no other fuel related problems. Spent over 3K for the fuel issue and the transmission was all covered under warranty. Not quite sure if all this sounds legit. Any feedback is appreciated.

I have a 2020 AT4 DuraMax 3.0 with 20K miles. Recently driving with window down and no radio when I noticed a very distinct knocking from the engine at low speed (20MPH) when the truck is downshifting or prior to a stop. It goes away when the brake or gas is applied. It is brief and intermittent (like 4-8 knocks mostly). Does not always happen but have had it do so on downhill stops as well as uphill. Have not yet been able to replicate on flat stop. Is this something I should be reaching out to service, or is it normal? Thanks for any guidance.

I called them and asked if they had done any of these repairs. They have not. I am going to Simi Valley GMC as the have done a few of these. The Service Advisor there was understanding and actually called me back to let me know he was ordering the specific caulking and hardware for my repair.

I am in your area. What dealership did you use for the repair?

Thanks. Is the illuminated check engine light normal?

Is it normal for the check engine light to come on during regen? I am 2 weeks in to my 2020 1500AT4 second tank of fuel and 1100 miles. Is there another indicator of regen happening?

Where do you find the build date?