bowtie2007

I have a friend that also has a 2020 Sierra diesel and he asked me about the bouncing feeling following the DPF recall. I'm not happy with the reprogramming from that recall.

I have a 2020 Sierra 2500 diesel with 54,000 miles. For the last several months, my truck has developed a subtle rhythmic bouncing when idling. Being in drive or park does not make a difference. I've also noticed a surging when there is constant throttle around 25 to 35mph. The RPMs do not seem to move with the surging. If I let off the throttle or give more throttle, it stops. Is anyone else experiencing these issues?

Many owners have had this leak. The frame at the top of the window develops cracks which begin to leak. I had a 2019 Sierra 1500 and now have a 2020 Sierra 2500. Both windows leaked. There is a TSB and a very long thread regarding the topic under the 1500 thread.

There is a TSB on that issue. I was having the same problem and this fixed it. I had to tell the dealer about it.

After a couple months, the shifting became less aggressive and the MPGs are similar at slower speeds. The biggest difference I noticed now is driving above 70mph. I used to get about 20 mpg driving 75mph. At those speeds, I'm lucky to get 18 now. The new programming seems to be set for optimal mpg between 55 and 65 mph.

I got the recall done a couple weeks ago and there is a noticeable difference in the way it drives. It operates like it is in a constant regen cycle. It holds lower gears more often, keeping the RPMs higher and lowering my fuel economy. It is also more aggressive on the downshifting when I let off the accelerator. This is how it felt during the regen cycle prior to the tcm update, except it happens all the time now. I verified with a scanner that I am not in a regen, i was at about 85% soot level. Stop and go traffic around town would get me around 14 to 15mpg before. Now, I am getting 11 to 12. On the highway at about 70mph, I was easily getting 20mpg or more. Now, it is more like 18 to 19mpg. I hope the transmission is still trying to figure things out and will get better.

I did not think about NHTSA but I have filed a complaint with the BBB and FTC claiming a violation of the written warranty. I don't know how they can have a cracked window frame and just put sealant over the cracks instead of a replacement part. I don't know anything about how class actions lawsuits work or I may have tried that. tbully, I'm glad you got the replacement window instead of the sealant!

The rear sliding glass window of my 2020 GMC Sierra 2500 developed a leak in January of 2021. It caused water to saturate the carpet under the rear seats and allowed water to enter the rear seatback storage compartments. TSB 18-NA-383 states the cause is from cracks developing in the rear sliding window plastic upper rail glass guide and the solution instructs dealers to put seam sealant over the cracks. Skip forward a year later and 3,000 miles out of factory warranty. The sealant failed and the window was leaking again. GM initially refused to pay anything and the dealer wanted $1,382.70 because they stated I needed a full rear window replacement. Extended warranty wouldn't cover it because it was not a mechanical breakdown. After a many calls to GM customer assistance, they agreed to cover 70% leaving me to still pay $414. This window leak is not isolated to just a few. I had a 2019 GMC Sierra 1500 in which the rear window leaked before I traded. A friend of mine has a 2020 GMC Sierra 2500 and his window is leaking. GM will try to put a bandage on the window cracks in the form of sealant instead of actually replacing the defective window. Many of the people in the forums report that the sealant does not last as was the case with mine. If you are unlucky enough to fall outside of warranty when the sealant fails, GM will not cover anything without a fight.

The rear sliding glass window of my 2020 GMC Sierra 2500 developed a leak in January of 2021. It caused water to saturate the carpet under the rear seats and allowed water to enter the rear seatback storage compartments. TSB 18-NA-383 states the cause is from cracks developing in the rear sliding window plastic upper rail glass guide and the solution instructs dealers to put seam sealant over the cracks. Skip forward a year later and 3,000 miles out of factory warranty. The sealant failed and the window was leaking again. GM initially refused to pay anything and the dealer wanted $1,382.70 because they stated I needed a full rear window replacement. Extended warranty wouldn't cover it because it was not a mechanical breakdown. After a many calls to GM customer assistance, they agreed to cover 70% leaving me to still pay $414. This window leak is not isolated to just a few. I had a 2019 GMC Sierra 1500 in which the rear window leaked before I traded. A friend of mine has a 2020 GMC Sierra 2500 and his window is leaking. There are hundreds of pages of forums in the 1500 forums regarding a leaking rear window. GM will try to put a bandage on the window cracks in the form of sealant instead of actually replacing the defective window. Many of the people in the forums report that the sealant does not last as was the case with mine. If you are unlucky enough to fall outside of warranty when the sealant fails, GM will not cover anything without a fight.

That could be from the window. Both my compartments had water in them from my window leaking.

I also got def quality warnings with blue platinum. Stopped using it and the messages haven't returned.

To comment on the 2500s, I came over to this forum because there is way more information on the leaking windows. I have a 2020 Sierra 2500 and the rear window first started leaking at 20,000 miles. The dealership sealed it but a year later, it has started leaking again. The sealant does not appear to be a long term fix.

My rear window was leaking when it had about 20,000 miles. The dealership followed the TSB and sealed it. It is about a year later and I just noticed today that it is leaking again. I haven't seen another TSB and it appears that they removed the old one. I'm afraid to bring mine back because they damaged my headliner last time and had to remove and replace my front windshield to get a new headliner in. At least they had loaners at that time.

Mine was doing this as well and i brought it in to the dealer. My repair order said, "replaced reducant reservoir with level sensor and harness, reset reducant level, reset nox catalyst reducant loading, enabled regeneration, and verified repair." Mine has been reading correctly since the repair. Side note... they had to order the parts and it took over a month to come in, it didn't happen in a day like it sounds.

I have an Imagine 2670mk and ran the camera wires underneath. No problems and it's been 2 years. I just ran it along the frame to the rear. Sent from my SM-G981U using Tapatalk