Looking at a Sierra 1500 19-21, NEED owner’s opinion

Dangelo · February 16, 2025

Looking to get a used Sierra 19-21 I have a 17 and it’s turned out to be more of a lemon then a sure thing and I still have 4 more years with it and since I’ve had it for two years now it’s been more times in the shop for this and that . Doesn’t help that it’s my DD . So I’d really like some input on owners with these years. I’m looking at an AT4. Should I stay clear or get ?

Joe Drives · February 16, 2025

I purchased a 2020 Silverado double cab 5.3 with the Z71 package new. I have 53,000 miles now and except for a couple early check engine lights resolved under warranty has been trouble free. I replaced the battery at 4 years old, normal oil changes usually between 10 and 20 % on the oil life monitor. Recently, I had a transmission service, transfer case service and brake fluid exchange. All services and battery were done at a dealer. I had the dealer install Rancho 9000 shocks and struts that I ordered from Rancho. Much less bounce, better ride than the stock Ranchos. I do not tow or haul heavy loads, but it is my daily transportation.

CamGTP · February 17, 2025

My opinion is the newer the better. Likely have less miles, less chance of first year problems and less wear.

Edited February 17, 2025 by CamGTP

Shall36 · February 17, 2025

I have a ‘21 AT4 with 6.2 and it’s the best vehicle I’ve had. Tons of power, nice ride, lots of features, super comfortable. I’ve had it for 3 years. I bought it used in January ‘22. No issues. Hasn’t been in the shop for anything. I will say that the stock Goodyear duratracs leave a bit to be desired and they are noisy.

Dangelo · February 17, 2025

4 hours ago, Joe Drives said:

I purchased a 2020 Silverado double cab 5.3 with the Z71 package new. I have 53,000 miles now and except for a couple early check engine lights resolved under warranty has been trouble free. I replaced the battery at 4 years old, normal oil changes usually between 10 and 20 % on the oil life monitor. Recently, I had a transmission service, transfer case service and brake fluid exchange. All services and battery were done at a dealer. I had the dealer install Rancho 9000 shocks and struts that I ordered from Rancho. Much less bounce, better ride than the stock Ranchos. I do not tow or haul heavy loads, but it is my daily transportation.

I have the 5.3 it’s been a good to me other then it being the 8 speed and the hard shifting from time to time. But I do like the new trail boss editions those are nice but thank you for the input I appreciate it

Transient · February 19, 2025

I have a 2020 Trail Boss LT with the 6.2 that currently has 77,000 miles. It's been trouble free. Only warranty work I recall having on it was the dash camera I got through GM Accessories that I had the dealer install before I took possession. They basically replaced the main module. Camera company is Thinkware. There was a tailgate bushing that was replaced under warranty. I also tried to have the dealer correct the reverse camera being slightly off angle, but that was unsuccessful and I pulled the plug on that project when GM told the dealer to replace the tailgate. I took the truck home and looked at the reverse camera assembly and came to the conclusion the issue was GM being cheap. Other than that, no issues aside from a few ghost CELs that resulted in nothing.

I do have a friend with a 2021 GMC Sierra AT4 with the 5.3. He told me he has the 10-speed in his truck. Less than a year ago the transmission failed on him and the dealer had to replace it with a new unit under warranty. I'm unaware of any other issues with his truck.

David Krueger · February 19, 2025

I have a 2021 GMC Sierra AT4 with a 3.0 Duramax. Bought it with 6,000 miles and now have about 43,000 on it. We love it. It rides nice, gets great fuel mileage and has plenty of power to pull/haul whatever I need it for. It has 20" wheels with Bridgstone Dueller A/T tires. Great tires. Recently had recalls for transmition shift module programming. The dealer took care of it. 1/2 hr. each time.

The one down side is, that I hate the mirrors. They are too small and DS has the convex in the top left corner. Hate that. PS mirror has " Objects appear closer " mirror. Hate that. Can,t back up a trailer and judge distance. I have looked into changing them with a OEM tow mirror but because I don't have the correct option in the BCM the dealer says that it can't be done.

hoitzed · February 21, 2025

I have a '19 AT4 with the 6.2. Just over 100k miles, towing through the mountains in the summer, DD grocery getting / kid limo in the winter. No issues so far. Oil changes according to DIC, did the transmission, front diff and rear diff fluids about 20k ago.

rcslotcar · February 28, 2025

My 2020 6.2L AT4 has been a great truck for me. The only two problems I've had since new was oxidation on the battery connections and whining noise. The battery connection looked good w/o corrosion, but needed to be polished due to lead oxidation on the terminals. The whining noise was a bad idler pully as discussed on this board. My truck is very low milage but is the most comfortable I've ever owned. I'm a very proud owner and get complements all the time and will not upgrade any time soon. Best of luck finding the right truck.

Dangelo · March 3, 2025

On 2/28/2025 at 4:30 AM, rcslotcar said:

My 2020 6.2L AT4 has been a great truck for me. The only two problems I've had since new was oxidation on the battery connections and whining noise. The battery connection looked good w/o corrosion, but needed to be polished due to lead oxidation on the terminals. The whining noise was a bad idler pully as discussed on this board. My truck is very low milage but is the most comfortable I've ever owned. I'm a very proud owner and get complements all the time and will not upgrade any time soon. Best of luck finding the right truck.

Yes sir…I appreciate your feedback TY

taze · March 6, 2025

I have a 21 RST Z71 6.2/10spd that's my daily. It's at about 39,000 miles with the only issue being a door lock actuator that started making noise just before 3/36 was up so I had it replaced. The 6.2/10spd combo is heaven on 4 wheels.

tjonesdfw · March 17, 2025

There's no consistency with this generation, so check it out closely and look at the repair history. I know someone who's had '19, '22 and now '24 6.2 trucks with minor warranty issues, and then another who had a '21 that blew two 6.2 motors. My '21 5.3 was in the shop more than I drove it for the first few years with multiple rear window leaks, camera issues repeatedly, mirror replacements, several parking sensor failures, check engine lights, wiring harnesses under the hood and in the rear, stereo/touchscreen failures, coolant leaks and more. All GM gave me for my "trouble" was a small discount on a new truck if I bought before the end of '25.