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GMC Sierra 2500Model year report

2020 GMC Sierra 2500 Problems

Compared with other GMC Sierra 2500 years

More complaints than typical for this model

98/100 3.1× a typical year · 50 = typical

Nearby years with a typical complaint level and no open NHTSA investigation: 2017, 2018, 2019, 2023

Based only on NHTSA complaints, recalls and investigations. Not adjusted for how many vehicles were sold, and not a reliability rating. How this is calculated

Complaints
79filed with NHTSA
Median mileage
31,800miles, 25 complaints with mileage
Recalls
9campaigns on record
Trend
RisingComplaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.

Sources: NHTSA records for the 2020 GMC Sierra 2500 (complaints, recalls, investigations). Report an error

What owners report

Owners of this model year most often describe transmission problems: harsh or erratic shifting, loss of power, and in some cases the rear wheels locking up. Many of those complaints relate to a transmission control valve recall, and some owners say shifting problems continued after the recall work. A second, earlier cluster of complaints covers brake noise and unintended braking at low mileage, plus rear-window and electrical faults.

  1. Transmission and drivetrain

    Transmission harsh shifting, loss of power, rear-wheel

    • 33 complaints (42%)
    • median 102,000 mi at 5.2 yrs old (15 state mileage)
    • filed 2019–2026

    Complaints describe hard or erratic shifting, delayed engagement, gear skipping, and sudden loss of motive power, sometimes while towing. Several owners report the rear wheels locking or the truck shuddering to a stop, and dealers have diagnosed transmission failure requiring replacement, in some cases with metal debris in the fluid. Owners also describe fluid leaks from a transmission cooler line and trouble getting recall parts. Some say shifting problems appeared or persisted after the recall software update. Mostly reported between roughly 100,000 and 125,000 miles, often during highway driving or while towing.

    Recall 24V797000Recall 26V0830001 related service bulletin

    What to check: Ask whether recalls 24V797 and 26V083 were completed and whether any transmission work or replacement was done. On a test drive, watch for harsh downshifts, delayed engagement, and any shudder at steady speed.

    2 excerpts from owner complaints in NHTSA records

    “My vehicle inadvertently locks the rear tires at highway speeds and then releases and drives. In some instances it may brake several times causing the tires to burn rubber for a short distance causing rear traffic to either swerve to avoid rear ending me and in a couple instances causes the rear following traffic to abruptly change lanes to avoid rear ending me”

    NHTSA complaint #11580026, filed 2024-03

    “After the transmission recall was completed, I’m now having erratic shifting. Having the recall adding software monitoring for a hardware issue is inadequate. Now that I am out of warrentee, gm has not resolved the issue and now I am having shifting problems.”

    NHTSA complaint #11661620, filed 2025-05
  2. Electrical system

    Battery drain and electrical/display faults

    • 16 complaints (20%)
    • median 100,000 mi at 2.1 yrs old (7 state mileage, few)
    • 2 mention a crash, fire or injury
    • filed 2020–2026

    Complaints describe batteries going dead after the truck sits, screens going blank, radio volume spikes, and lights or tailgate switches behaving intermittently. Some owners link a low-voltage condition to reduced-power or limp mode. Dealers reportedly ran updates or replaced a battery without resolving the concern in several cases. Reported from a few hundred miles up to around 35,000 miles.

    Recall 24V0600003 related service bulletins

    What to check: Check both batteries and their age, test the infotainment screen and radio, and confirm the tailgate and lights work consistently. Ask whether any battery or module repairs have been done.

    2 excerpts from owner complaints in NHTSA records

    “As I was driving home my check engine light came on and all of my lights went out. I had no tail lights and the radio started saying no signal detected. The dash screen was saying service keyless entry system. And I had no running lights but my headlights. Pretty scary thinking no one could see me as they were driving behind me at a high rate of speed. My truck only has 200 miles on it so this is really scary to be having issues so early in the ownership of this truck. …”

    NHTSA complaint #11362480, filed 2020-10, 212 miles

    “The screen on my truck has gone blank several times and the volume on the radio goes super load and the only way to stop it seems to be to stop and turn off the truck, open the doors and re start truck. Today, I couldn't get my screen to go off in my truck when I turned it off, I tried turning off, restarting etc but to no avail. I'm at work now and fear that the battery will go dead before I get off work. I just had the truck at Gmc 2/6/2021 and was told that their were no recalls. …”

    NHTSA complaint #11396147, filed 2021-02, 8,501 miles
  3. Brakes

    Brake noise and unintended automatic braking

    • 11 complaints (14%)
    • median 33,500 mi at 2.8 yrs old (6 state mileage, few)
    • filed 2019–2026

    Owners report loud brake squealing from new, with dealers describing it as normal or quoting a pad replacement at the owner's cost. Others describe the brakes engaging on their own at low speed, the parking brake applying unexpectedly, or rear calipers seizing, with the dealer sometimes unable to duplicate the concern. One owner towing a trailer reported overheated rotors and a burning smell. Mostly reported at very low mileage, often within the first few thousand miles.

    Recall 21V5780001 related service bulletin

    What to check: Listen for brake squeal on a cold start and ask whether pads or calipers have been replaced. Ask whether the parking brake or automatic braking has ever engaged without input.

    2 excerpts from owner complaints in NHTSA records

    “My brakes are squeaking very loudly they have been since august. I was driving down the road on us1 and prepared to stop to make a turn and my truck would not stop. I was making a right turn and ended up in the other lane of oncoming traffic sideways because I tried to turn my truck to slow it down. I complained about my brakes several times to the dealership they ordered me new brakes without even looking at my vehicle around august 8th. We are now at the last two days of september and they still do not know when the brakes will come in. …”

    NHTSA complaint #11361606, filed 2020-09, 5,000 miles

    “While driving my 2020 GMC 2500 Denali with the Duramax Diesel engine, the power assist for the steering and brakes failed without any warning. This made the truck nearly impossible to steer and stop. Luckily, I was able to avoid a collision and get the truck stopped in a safe location. The truck is currently being towed to Rivard GMC in Tampa, Fl. Doing an internet search, I found this problem has happened to others as well. Please ask GM to rectify this extremely dangerous defect.”

    NHTSA complaint #11421278, filed 2021-06
  4. Body and structure

    Rear window and roof area water leaks

    • 7 complaints (9%)
    • median 69,000 mi at 4.6 yrs old (1 states mileage, few)
    • filed 2023–2026

    Owners describe water entering the cab through the rear sliding window, with saturated seats and carpet, a moldy odor, and in some cases a cracked aluminum frame around the window. Complaints say the dealer attributed it to a design or sealing issue and that repairs were quoted or described as temporary. A few also mention leaks around the rear roof spoiler area. Reported across a wide mileage range, from low-mileage trucks to around 69,000 miles.

    1 related service bulletin

    What to check: Inspect the headliner, rear seat, and carpet under the rear window for stains or dampness, check for musty smell, and ask whether the rear window or its seal has been replaced.

    2 excerpts from owner complaints in NHTSA records

    “Rear sliding window leak and has saturated seat and carpet causing an unhealthy environment. Spoke with dealer and was told it is a design flaw and repairs are not covered under extended warranty. I was also told it is only a temporary fix and “ leak will reoccur”. I only realized of the problem when soap residue was seen on the inside of the widow. Dealer gave estimate of repair.”

    NHTSA complaint #11547265, filed 2023-09

    “My rear spoiler roof area leaks. This is something GM knows about and has sent out memos to dealers. To fix this it’s around $1000. I think GM should fix a problem they have been well aware of for sometime.”

    NHTSA complaint #11769733, filed 2026-10

Buying note. Have any open transmission recalls checked and completed before purchase, and drive the truck at highway speed and while towing if possible to look for shifting problems. Also inspect the rear window area for leaks and confirm the brakes and batteries are in good condition.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.

NHTSA recorded 79 consumer complaints for the 2020 GMC Sierra 2500. 25 of the complaints include a mileage, and 52% of those were filed for vehicles with under 50,000 miles; the median is 31,800 miles. Of all complaints, 1 involved a crash, 3 a fire, 1 an injury, according to the filers. NHTSA lists 9 recall campaigns and 1,391 technical service bulletins for this model year. Compared with the other 14 GMC Sierra 2500 model years that have at least 25 complaints and are old enough to compare, this one scores 98 out of 100, where 50 is a typical year for the model (more complaints than typical for this model). The comparison allows for the era and for how long each year has had to collect complaints, but not for how many vehicles were sold.

Which parts are reported most

Complaints can name more than one part, so the counts add up to more than the total. Select a part to see its complaints, recalls and bulletins.

Also reported: Exterior lighting (2), Fuel system (2), Tires (2), Wheels (2), Air bags (1), Back-over prevention (rear camera) (1), Electronic stability control (1), Suspension (1), Visibility (wipers, defrost, mirrors) (1).

Example complaints

Transmission and drivetrain: “A couple times I heard loud clanking coming from rear brakes. One time in particular I was trying to stop and it felt line someone had ran into my truck but must have been the rear wheel locking up”

NHTSA complaint #11718162, filed 2026-02

Other or unknown: “The front park assist sensors on this truck do not operate as intended, or as on prior years or as on other vehicles. The sensors did not pick up parking bollards in front of a convenience store and resulted in a minor ding that cost over $1300 to repair. When bumper was repaired the service person said sensors were fixed, yet, to his surprise, we were able to inch up to a car directly intersecting the front of the car and it did not pick it up. I did a similar test with a brand new/unsold vehicle on dealer lot ind it failed to sense the large truck directly in front of it. …”

NHTSA complaint #11330146, filed 2020-06, 4,500 miles

Electrical system: “Went out to my vehicle that has been sitting in my driveway for 24 hours and attempted to unlock it with the key fob. Nothing. Tried the other fob. Nothing. Used the key to unlock the door and get in to push button start and nothing. I plugged both batteries into chargers and they would start to charge, then discharge after the batteries got up to about 20% I called Gmc roadside assistance and they sent someone out. The service guy showed up about 45 min later and hooked up a jump box to each battery. Still no luck in getting it started. He said it must have some major electrical issues. …”

NHTSA complaint #11382789, filed 2020-12, 9,200 miles

Brakes: “Brakes since new squeeled. Took to dealer and dealer said it was normal. Have had the truck about 11 months now. Dealer stated GM now uses a different pad material and I would have to pay for it at a cost of close to $1,000 to replace the pads.”

NHTSA complaint #11390937, filed 2021-02, 1,000 miles

Mileage when problems were reported

52% of the 25 complaints with a mileage were filed for vehicles with under 50,000 miles; the middle half falls between 5,000 and 107,000 miles.

40%0–104%10–258%25–508%50–750%75–10036%100–1504%150+
Share of complaints by mileage when the problem was reported, in thousands of miles (25 complaints with mileage). Red bars: under 50,000 miles. Bucket widths differ. Median: 31,800 miles.

Complaints by year filed

Trend: rising. Complaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.

2019202020212022202320242025292026
Complaints by year the complaint was filed with NHTSA. Red bars: the last 3 full calendar years used for the trend. The current year (2026) is partial.

Recalls and investigations

See all 9 recalls for the 2020 GMC Sierra 2500 → · Check a VIN at nhtsa.gov/recalls

Technical service bulletins

TSBs are manufacturer notes to dealers about known repair procedures. They are not recalls and do not by themselves mean a vehicle has a fault. 1,391 on record; the latest 10 are shown.

See all 1,391 bulletins →

Other model years of the GMC Sierra 2500

YearComplaintsMedian miRecallsCrash ★MPGScore (50 = typical)Trend
2026139,0001———Too new
2025281,3001——Too new to compareToo new
20241079,9044——Too new to compareToo new
20233334,0001——40 · TypicalToo new
20224515,1673——65 · MoreRising
20215253,0006——69 · MoreRising
20207931,8009——98 · MoreRising
20193228,72974—50 · TypicalRising
20183510,00054—52 · TypicalFalling
20173722,06064—53 · TypicalFalling
20165929,50064—64 · TypicalStable
20158937,02363–4—93 · MoreFalling
20143039,00022–4—10 · FewerFalling
20134660,00032–4—0 · FewerStable
20123168,50033–4—2 · FewerRising
20116355,4004——34 · FewerFalling
20101077,0005———Not enough data
20093139,6005——39 · TypicalFalling
20086367,5003——17 · FewerFalling
20078370,0003——Not compared (before 2008)Rising
20066643,5001——Not compared (before 2008)Falling
200511560,0001—11Not compared (before 2008)Falling
200414360,0001——Not compared (before 2008)Falling
200316073,0000——Not compared (before 2008)Falling
200213485,5001——Not compared (before 2008)Rising
200113465,0002——Not compared (before 2008)Stable
20004891,0001—15Not compared (before 2008)Stable
199936100,0000—15Not compared (before 2008)Stable
19981547,0001—15—Stable
199714100,0002—15—Not enough data

All GMC Sierra 2500 model years · Best and worst years by complaints

Frequently asked questions

What are the most common problems with the 2020 GMC Sierra 2500?

Owners of this model year most often describe transmission problems: harsh or erratic shifting, loss of power, and in some cases the rear wheels locking up. The issues reported most often: Transmission harsh shifting, loss of power, rear-wheel; Battery drain and electrical/display faults; Brake noise and unintended automatic braking.

How many NHTSA complaints does the 2020 GMC Sierra 2500 have?

NHTSA recorded 79 consumer complaints for the 2020 GMC Sierra 2500 as of Oct 29, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.

What part of the 2020 GMC Sierra 2500 is reported most often?

Transmission and drivetrain is named most often, in 25 complaints (32% of the total), followed by other or unknown with 18.

Has the 2020 GMC Sierra 2500 been recalled?

NHTSA lists 9 recall campaigns for this model year. To check a specific vehicle, enter its VIN at nhtsa.gov/recalls.

At what mileage are problems with the 2020 GMC Sierra 2500 reported?

Among the 25 complaints that include a mileage, the median is 31,800 miles and the middle half falls between 5,000 and 107,000 miles; 52% were filed for vehicles with under 50,000 miles.

About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 29, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.

Complaint counts come from NHTSA’s public complaint database; we count each complaint once. The source records for this vehicle are on nhtsa.gov. Scores and trends are our own summaries of that data, described in the methodology. This page is not legal, safety or repair advice: for a specific vehicle, check its VIN at nhtsa.gov/recalls and ask a qualified mechanic. See an error? Tell us.