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Used 2021 GMC Sierra 1500 Diesel Consumer Reviews

3.5 out of 5 stars
12 reviews

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Cons
1 out of 5 stars

Broke down at 1,236 miles

Let down, 01/16/2021
2021 GMC Sierra 1500 AT4 4dr Crew Cab 4WD 6.6 ft. SB (3.0L 6cyl Turbodiesel 10A)
80 of 90 people found this review helpful

Bought a 2021 AT4 with 3.0L Duramax. Ordered it and waited 4 months for it to arrive. Love the ride & engine. Had to be towed to dealer with 1,236 miles due to a "transmission module issue." Been 3 days haven't heard back. Think transmission might've blown. Wouldn't go in reverse, would go into reverse position but wouldn't move. Engine power was reduced & check engine light came on. The 10 speed transmission was supposed to be solid.... be cautious

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5 out of 5 stars

Very pleasing to drive.

Howard Beck, 10/13/2021
2021 GMC Sierra 1500 AT4 4dr Crew Cab 4WD 6.6 ft. SB (3.0L 6cyl Turbodiesel 10A)
13 of 14 people found this review helpful

Have 6,000 miles on and not a single problem. Handles great. Love the multi-pro tailgate, makes it so easy to use truck. interior is easy to use all to options. Have the 3.0L great power. Wish I could turn off completely the auto off feature.

Safety
5 out of 5 stars
Technology
5 out of 5 stars
Performance
5 out of 5 stars
Interior
5 out of 5 stars
Comfort
5 out of 5 stars
Reliability
5 out of 5 stars
Value
5 out of 5 stars
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2021 GMC Sierra 1500 for sale near you
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5 out of 5 stars

Great Pickup

Laban, 05/01/2021
updated 11/07/2022
2021 GMC Sierra 1500 AT4 4dr Crew Cab 4WD 6.6 ft. SB (3.0L 6cyl Turbodiesel 10A)
15 of 21 people found this review helpful

GMC six cylinder deiseal is smooth, great towing, fuel efficient vehicle. But with Diesel $1.00 to $1.25 more than Regular gas - I am hurting.

Safety
5 out of 5 stars
Technology
5 out of 5 stars
Performance
5 out of 5 stars
Interior
5 out of 5 stars
Comfort
5 out of 5 stars
Reliability
5 out of 5 stars
Value
5 out of 5 stars
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1 out of 5 stars

New truck big burner out pile of trash

Mark Dupont, 04/18/2021
2021 GMC Sierra 1500 AT4 4dr Crew Cab 4WD 6.6 ft. SB (3.0L 6cyl Turbodiesel 10A)
25 of 41 people found this review helpful

Bought a 2021 GMC Sierra sky. All the bells and whistles. Had it 5 months with 3400 miles. Came back from store and parked it in driveway. Went in the house and my wife said your truck is smoking. Ran out and flames under hood. Five minutes later entire front end of truck engulfed in flames. Total loss. I was just lucky I was out of it. No indication of problems while driving.

Safety
1 out of 5 stars
Technology
1 out of 5 stars
Performance
4 out of 5 stars
Interior
3 out of 5 stars
Comfort
2 out of 5 stars
Reliability
1 out of 5 stars
Value
1 out of 5 stars
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5 out of 5 stars

GMC AT4 Diesel CarbonPro Series

Scott M, 03/16/2021
2021 GMC Sierra 1500 AT4 4dr Crew Cab 4WD 6.6 ft. SB (3.0L 6cyl Turbodiesel 10A)
13 of 24 people found this review helpful

You can't get a truck with more luxury, more add-ons, better mileage, and power. This thing rocks and overall, cannot be beat. I love it and I have only had it a couple of days. I cant wait to put it through it paces and see what else this thing can do. Thanks to Nyle Maxwell GMC located in Round Rock, Texas for an amazing on an amazing truck.

Safety
5 out of 5 stars
Technology
5 out of 5 stars
Performance
5 out of 5 stars
Interior
5 out of 5 stars
Comfort
5 out of 5 stars
Reliability
5 out of 5 stars
Value
5 out of 5 stars
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