Is the 2021 Gmc SIERRA 2500 reliable?

The 2021 Gmc SIERRA 2500 has 60 complaints filed with NHTSA (1.2x the segment average). Our reliability verdict: average. Most common issue: TRANSMISSION problems.

What are common problems with the 2021 Gmc SIERRA 2500?

Top problems: TRANSMISSION (11 complaints, avg repair $500); LIGHTING (9 complaints, avg repair $500); ENGINE (7 complaints, avg repair $500). Issues typically appear around 50K miles.

Are there any recalls on the 2021 Gmc SIERRA 2500?

Yes, there are 6 recall(s): TIRES:TEMPORARY/EMERGENCY SPARE TIRE, SERVICE BRAKES, HYDRAULIC:POWER ASSIST:ELECTRIC:CONTROL MODULE, SEAT BELTS, SEAT BELTS, LATCHES/LOCKS/LINKAGES:TAILGATE:LATCH, POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE. Contact any Gmc dealer to verify if recalls have been completed on your specific vehicle.

How much does it cost to insure a 2021 Gmc SIERRA 2500?

Estimated US average full-coverage insurance for the 2021 Gmc SIERRA 2500 is approximately $1,687/year (sedan-midsize class). Actual quotes vary heavily by state, driver age, driving record, and credit — see the interactive insurance estimator on this page for state-specific pricing.

2021 Gmc SIERRA 2500

Problems, Recalls & Reliability Report

Average

Quick Summary

The 2021 Gmc SIERRA 2500 has 60 owner complaints filed with NHTSA — that's 1.2x the segment average of 52. The most common issue is transmission problems (18% of all complaints), specifically: the owns a 2021 gmc sierra 2500. the contact stated while driving 70 mph, the rpm revved up to 6,000 rpm. additionally, the vehicle lost motive power. the vehicle was taken to the dealer, who informed the contact that the transmission needed to be replaced. the vehicle was not repaired. the manufact. There are 6 recalls issued for this model year. ⚠️ 2 fire reports filed.

2 fire reports 5 crash reports 1 injury

Total Complaints

Recalls Issued

—/5

Safety Stars

1.2x

vs Segment Avg

Known Problems(top 5 of 8)

TRANSMISSION

11 complaints

18%

• The owns a 2021 GMC Sierra 2500. The contact stated while driving 70 MPH, the RPM revved up to 6,000 RPM. Additionally, the vehicle lost motive power. The vehicle was taken to the dealer, who informed the contact that the transmission needed to be replaced. The vehicle was not repaired. The manufact
• The transmission started lurching and surging power while driving
• The contact owns a 2021 GMC Sierra 2500. The contact stated while driving approximately 70 MPH, the vehicle lost motive power. The contact stated that the message “Vehicle will not Exceed 50 MPH" was displayed. The vehicle was taken to a dealer and remained for over four months after being diagnosed

Typical onset: 50K miles Est. repair: $500💥 1 crashes

“The owns a 2021 GMC Sierra 2500. The contact stated while driving 70 MPH, the RPM revved up to 6,000 RPM. Additionally, the vehicle lost motive power. The vehicle was taken to the dealer, who informed the contact that the transmission needed to be replaced. The vehicle was not repaired. The manufact”

— NHTSA complaint filing

When Problems Appear on the 2021 Gmc SIERRA 2500

Based on 17 owner complaints that included an odometer reading. Median mileage at time of complaint: 53K miles. Most complaints cluster in the 30-60K miles range.

Overall complaint distribution by mileage

0-30K

30-60K

60-100K

100-150K

150-200K

200K+

Mileage figures are self-reported by owners in NHTSA complaint filings. Peak bucket = the mileage range with the most complaints for that component; it reflects when owners noticed and reported problems, not necessarily when the fault first occurred.

Recalls (6)

TIRES:TEMPORARY/EMERGENCY SPARE TIRE29/07/2021

General Motors, LLC. (GM) is recalling certain 2020-2021 Chevrolet Silverado 2500 and GMC Sierra 2500 vehicles equipped with a 17" spare tire (RPO ZHQ or ZXT) and either the 20" accessory road tire (RPO REM) or the 18" accessory road tire (RPO Q2V). Operating the spare tire with other 20" or 18" tires can prevent the Anti-Lock Braking System (ABS) from engaging.

Risk: An ABS system that cannot control the rear wheels independently increases the risk of a crash.

Fix: Dealers will provide the appropriate spare tire and apply a new spare tire information label, free of charge. Owner notification letters were mailed on October 18, 2021. Owners may contact Chevrolet customer service at 1-800-222-1020; GMC customer service at 1-800-462-8782. GM's number for this recall is N212329780.

Estimated Insurance Cost for 2021 Gmc SIERRA 2500

Estimate only, not a quote. Modeled from NAIC + HLDI averages for a hypothetical 35-year-old driver with clean record + full coverage. Your actual quote depends heavily on your age, driving history, credit, ZIP code, and insurer.

Your state (affects local premium average)

Full coverage / year

$1,687

Full coverage / month

$141

Liability only / year

$611

vs US avg

+1%

How this estimate is calculated

US base full-coverage premium$1674

× state (US)1.00x

× vehicle class (sedan-midsize)0.96x

× theft risk1.00x

× safety rating1.00x

× vehicle age1.05x

= Full coverage estimate$1687

Coverage assumed: 100/300/100 liability + comprehensive/collision, $500 deductibles. Data sources: NAIC 2024 + HLDI loss studies.

Maintenance & Warranty

Recommended Gmc SIERRA 2500 Service Intervals

Oil change

8K mi / 12 mo

Tire rotation

8K mi

Brake fluid

36 months

Transmission fluid

45K mi

Engine coolant

150K mi

Spark plugs

100K mi

Cabin air filter

23K mi

Engine air filter

45K mi

Differential (AWD/4WD)

45K mi

Uses GM Oil Life System. Full-size trucks may have shorter differential and transfer case intervals if used for towing.

"Severe service" conditions (heavy towing, extreme temps, city stop-and-go) typically halve these intervals. Always consult your vehicle's owner's manual for the authoritative schedule.

Gmc New-Vehicle Warranty Coverage

Bumper-to-bumper (basic)

3 yr / 36K mi

Powertrain

5 yr / 60K mi

Hybrid/EV battery

8 yr / 100K mi

Corrosion (rust perforation)

6 yr / 100K mi

Roadside assistance

5 yr / 60K mi

These are the terms for a new Gmc. If you're buying a used 2021 SIERRA 2500, remaining coverage is usually pro-rated from the vehicle's original in-service date. Not all coverage transfers between owners — check with a Gmc dealer for VIN-specific remaining warranty.

Estimated Repair Costs

TRANSMISSION(~50K mi)

$500

LIGHTING(~50K mi)

$500

ENGINE(~50K mi)

$500

ELECTRICAL(~50K mi)

$500

BRAKES(~50K mi)

$500

Estimates based on average reported repair costs. Actual costs vary by location, shop, and severity.

🔍 Pre-Purchase Inspection Checklist

Based on 60 owner complaints for this specific year, here's what to check or ask about:

☐
TRANSMISSION: The owns a 2021 GMC Sierra 2500. The contact stated while driving 70 MPH, the RPM revved up to 6,000 RPM. Additionally, the vehicle lost motive power. The vehicle was taken to the dealer, who informed the contact that the transmission needed to be replaced. The vehicle was not repaired. The manufact
Typically appears around 50K miles. Repair cost ~$500
☐
LIGHTING: Passenger headlight light fills up with moisture resulting in the HID module filling up with water and shorting out. The high beam starts flashing when you try to use your turn signal and eventually the headlights completely stop working. Is a known problem, but GM won’t do anything to help if you’r
Typically appears around 50K miles. Repair cost ~$500
☐
ENGINE: THE TRUCK IS PARKED AT DEALERSHIP
Typically appears around 50K miles. Repair cost ~$500
☐
ELECTRICAL: While driving the entire dash cluster (speed,rpm etc) turns off entirely, reloads as if truck is just starting with all lights coming off and on, needles cycling max/min. Unable to recreate on command, multiple others reported same issue with no cause/cure listed.
Typically appears around 50K miles. Repair cost ~$500
☐
RECALLS: Verify all 6 recalls have been completed — free at any Gmc dealer
☐
General: Get a pre-purchase inspection from an independent mechanic ($100-$200)