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Used
2021 GMC Sierra 2500 AT4 trucks
for sale
near me
- Down Payment
- $0
- Net trade-in value
- $0
- Months
- 72
- APR
- 7.0%
- Sales tax
- 0.0%
*Estimated payments are calculated by Cars.com and are for informational purposes only. We’ve estimated your taxes based on your provided ZIP code. These estimates do not include title, registration fees, lien fees, or any other fees that may be imposed by a governmental agency in connection with the sale and financing of the vehicle. Other taxes may apply. They do not represent a financing offer or a guarantee of credit from the seller. Actual terms vary by lender.
**Your Saved Vehicles list will be shared along with your contact information when you submit a vehicle request to a dealership. To opt out of this sharing, please view your options on Cars.com Privacy Notice.
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
Beautiful truck
I love my 2021 GMC Denali 2500HD. I have gotten more complements on this truck than any other vehicle that I have owned. I get great highway fuel milage average 19-26mpg,which is great for a heavy duty truck!
Certified
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
King ranch
I have purchased many vehicles from Mcmullen Ford. They are always friendly and professional. They treat me fairly on the price. They deliver my vehicle to me.
Best truck I ever owned
Love my GMC. Owned a Chevy and this absolutely beats it hands down. Never had any issues. Inside is very comfortable and can't imagine driving anything else
Vehicle information
Features
Reviews
The customer service, the compassion and understanding
The customer service, the compassion and understanding were truly great. Suzanne and Jason were incredibly kind, very responsive and explanatory and provided us with all around amazing service. We were contacted quickly after our online inquiry and Suzanne was happy to help us answer all the questions we had. We are out of state and the process in which the paperwork and transport of the vehicles were done was flawless. We thank you all for your expertise and kindness. We will be back when the time comes and will most certainly refer all who are in the market to your dealership.
GMC 2500 HD AT4
This is the first diesel I have owned. The power is amazing and I really like the room inside the cab. This truck is a beast... Love it!
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
I had a great experience coming in for an oil change.
I had a great experience coming in for an oil change. The drop-off process was quick and convenient, and they even offered me a ride to work, which I appreciated, although my job is close enough that I chose to walk. My appointment was at 9:00 AM, but I dropped my car off at 8:00 AM before heading to work, and by 10:15 AM they had already called to let me know it was finished. The service was fast, efficient, and everyone was very friendly. I have always been treated wonderfully anytime I?ve had my vehicle serviced here. Highly recommend! ?????
Never had one. Always wanted one and love it.
I love my Denali. Beautiful truck inside out. When I drive down the road all heads turn. I couldn't have made a better choice. That's Cortez for you good service.
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
Staff were very kind and the job was completed in a
Staff were very kind and the job was completed in a timely and reasonable manner.
Early to tell truck has less than 100 miles
Truck was bought specifically to our travel trailer. We have to wait for 1000 break in before we can tow the trailer. So far the truck is very quiet, smooth running, & comfortable to drive. We were pleasantly surprised at how much interior storage space is available. Having the bed steps before rear tires and in the bumper sides is very nice. Bed rails are even with my shoulders so the steps get used a lot.
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
Very polite and nice salesman.
Very polite and nice salesman.Answered all my questions. and it hadn't been so far away from where I am living I probley would have test drove the 2017 Kia Sorento they had.
GMC Certified
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
I Don?
I Don?t Trust My Car With Anyone Else. When I First Started Going There, They Were So Polite. They Made My Us Feel At Home. I Never Go Where I Don?t Feel Welcomed. Awesome, Staff
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
Mike Rose was our hero when we were looking for a almost
Mike Rose was our hero when we were looking for a almost new Tahoe. We were in Hickory and Morganton area, we were looking at a Tahoe at another Large dealer in Hickory, they SOLD it while we were looking! Called Mike Rose at Parks GMC and he took our name and number late February, 3rd He told us what he had on the lot and held it for us overnight. We arrived Feb 4th. to look at the 2025 Tahoe, High Country. We agreed on price and we drove it home. Love Mike Rose's attention to detail, southern charm, very nice, going above and beyond to help us. He was patient teaching us the new buttons and devices on the High Country Tahoe. We will purchase another new vehicle from him next week. People are important! Mike listened and treated us with respect and Southern Hospitality when we were looking for a vehicle.
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
David was excellent to work with, he was very
David was excellent to work with, he was very knowledgeable about the Equinox and was able to answer all my questions. He made going through all the paperwork easy and we will definitely want to work with him again.
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
Everyone is so helpful.
Everyone is so helpful. They made the buying process as easy as possible. I would recommend this dealership. I will definitely be buying there in the future.
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
mia was great to work with and I'll recommend all my
mia was great to work with and I'll recommend all my friends and family to her.
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
Very helpful and I really liked the truck, but the
Very helpful and I really liked the truck, but the dealership was just too far from Colorado.
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
The personnel - friendly and professional Appreciate
The personnel - friendly and professional Appreciate your working with us to reach a deal that is comfortable
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
I was in and out in 90 minutes from when I arrived
I was in and out in 90 minutes from when I arrived driving my newer Jaguar. Steve and Brad saw that I got my dream car.
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
Avery was an amazing sales consultant.
Avery was an amazing sales consultant. He made me feel very comfortable with the whole process. It felt like I was talking to a trusted family member. I would highly recommend Walser Mitsubishi because of Avery and his amazing customer service. He is a rare gem, for sure! Caleb was also very helpful and professional!
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
The entire experience at Sheehy was awesome!
The entire experience at Sheehy was awesome! From Kevin, the sales representative, to Clint, the manager, my entire deal was treated as if it was their own! They made every decision in favor of the buyer to make it feel I was being taken care of and treated right! Highly recommend the entire team at Sheehy VW in Hagerstown!
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
Great Service!
Great Service! Dominic and Mike are very helpful and are happy to answer all my questions.
Vehicle information
Features
Reviews
We had a great car buying experience with Friesen Ford.
We had a great car buying experience with Friesen Ford. Louie and his team were extremely professional and wonderful to work with. We purchased a used Expedition that had some unexpected problems come up several days after the purchase. I notified Louie and his team corrected the issues right away (free of charge). We love our Expedition and will definitely recommend Friesen Ford to others!
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
Excellent.
Excellent. It is my fourth new car purchase from them. They take good care of me. Xxxxxx xxxxxx xxxxxx xxxxxx xxxxxx xxxxxx xxxxx xxxxx xxxxxxx
Used
2021 GMC Sierra 2500 AT4
Vehicle information
Features
Reviews
Excellent service, they kept me informed on how the
Excellent service, they kept me informed on how the repairs were going and was even offered by more than one employee the use of a dealer car while I waited. Very friendly staff and waiting room was nice.
GMC Sierra 2500 prices by year
| Model year | Average price | Deals |
|---|---|---|
| 2026 GMC Sierra 2500 AT4 | 8 Great deals | |
| 2025 GMC Sierra 2500 AT4 | $74,962 | 13 Great deals |
| 2024 GMC Sierra 2500 AT4 | $70,116 | 8 Great deals |
| 2023 GMC Sierra 2500 AT4 | $57,526 | 26 Great deals |
| 2022 GMC Sierra 2500 AT4 | $55,317 | 31 Great deals |
| 2020 GMC Sierra 2500 AT4 | $50,322 | 40 Good deals |
About the 2021 GMC Sierra 2500 AT4
AT4 shown.
- Seating
- 5
- Door count
- 4
- Drivetrain
- Four Wheel Drive
- Combined MPG
- 0
- Transmission
- 6-Speed A/T
- Engine
- 445.0-hp, 6.6-liter, 8 Cylinder Engine (Diesel Fuel)
How much does the 2021 GMC Sierra 2500 AT4 cost?
The 2021 GMC Sierra 2500 AT4 price depends on several factors, including optional features, mileage, vehicle history and location. The nationwide average price for a 2021 Sierra 2500 AT4 is $52,371, with pricing starting at $39,455.
What are some similar vehicles and competitors of the 2021 GMC Sierra 2500 AT4?
The 2021 GMC Sierra 2500 AT4 compares to and/or competes against the following vehicles:
Is the 2021 GMC Sierra 2500 AT4 reliable?
The 2021 GMC Sierra 2500 has an average reliability rating of 4 out of 5 according to Cars.com consumers. Find real-world reliability insights within consumer reviews from 2021 Sierra 2500 owners.
75% of drivers recommend this car
- Comfort
- 4.7
- Interior
- 4.6
- Performance
- 4.3
- Value
- 3.9
- Exterior
- 4.6
- Reliability
- 4.0
AT4 (2 styles)
| Style | |
|---|---|
| 4WD Crew Cab 172" AT4 | 4WD Crew Cab 159" AT4 |
| Inventory price | |
| Starting at $59,300 | Starting at $59,100 |
| Combined MPG | |
| 0 | 0 |
| Engine | |
| 445.0-hp, 6.6-liter, 8 Cylinder Engine (Diesel Fuel) | 445.0-hp, 6.6-liter, 8 Cylinder Engine (Diesel Fuel) |
*Estimated payments are calculated by Cars.com and are for informational purposes only. We’ve estimated your taxes based on your provided ZIP code. These estimates do not include title, registration fees, lien fees, or any other fees that may be imposed by a governmental agency in connection with the sale and financing of the vehicle. Other taxes may apply. They do not represent a financing offer or a guarantee of credit from the seller. Actual terms vary by lender.
**Your Saved Vehicles list will be shared along with your contact information when you submit a vehicle request to a dealership. To opt out of this sharing, please view your options on Cars.com Privacy Notice.
GMC Sierra 2500 trims
-
GMC Sierra 2500 2021 Denali
14 Great Deals out of 173 listings starting at $36,995
-
GMC Sierra 2500 2021 Base
6 Great Deals out of 39 listings starting at $23,495
-
GMC Sierra 2500 2021 SLT
4 Great Deals out of 34 listings starting at $32,987
-
GMC Sierra 2500 2021 SLE
4 Great Deals out of 28 listings starting at $31,900
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This vehicle is certified pre-owned, backed by a manufacturer warranty, and typically undergoes a rigorous multi-point inspection to ensure quality and reliability.
This vehicle is currently in high demand given its competitive price, desirable features, and overall condition, and may have a higher chance of selling quickly.