2021 Gmc SIERRA 3500: complaints, problems and recalls

Trailer brake wiring connection continually disconnectsthen reconnects some time later. Some periods of up to 10 minutes without having trailer braking power. Major safety issue when toeing fifth wheel trailer. We lost brakes going down steep grades. GMC is aware of issue, but has not provided a solution. Vehicle has been yo service shop with no resolution. Case has been opened with GMC.

Owner-reported narrative. Look up ODI 11420443 at NHTSA ↗

The vehicle recently had a recall repaired at the dealership. I subsequently took delivery on it as a BRAND NEW UNIT, and the brakes are extremely soft; to the point where I must depress the pedal to the floor to get it stopped even at slow speeds. I hoped it was just an air bubble from the repair; but the fluid levels are full and the dealer had no ideas on what could be wrong at this point. I have a great relationship with this dealer, and we’ll continue working on it. But GM is releasing absolute trash lately and I fear that some poor fami…

Owner-reported narrative. Look up ODI 11438295 at NHTSA ↗

Tailgate falls open while traveling down the road

Owner-reported narrative. Look up ODI 11446957 at NHTSA ↗

•The diesel exhaust fluid heater is a faulty component in the system, there is a back order on the part with no ETA • My pickup only does 55MPH right now and soon to do 5MPH you cannot drive on a public road doing 5MPH •There is thousands of other people having the same exact problem! •The DEF light is illuminated on my dash along with the check engine light, when you diagnose the error code it comes up with “P20C1 Reductant Heater C Control Circuit/OPEN”

Owner-reported narrative. Look up ODI 11454519 at NHTSA ↗

The throttle body gets stuck wide open after the eninge gets up to operating temperature, it will give some warning with the throttle like on off throttle use and no codes show up at all. The risk of everyones is in extrem DANGER. The break are to soft and well not stop unless you put both feet on the break pedal down to the floor. Tranismission can NOT figure out what gear it needs to be in way too many gears and horrible fuel mpg for the 6.6L Duramax L5P. None of the GM dealership will look at the truck unless there is a code or it is happeni…

Owner-reported narrative. Look up ODI 11455361 at NHTSA ↗

Part Number: 85138746 - DEF tank assembly, heater, pump, reservoir. I was told there were issues with the heater and pump. The heater turns high or the heater won’t work; and there are issues with the connector.02/24/22: My truck has 16,000 approx. miles. The check engine light came on and displayed message that I had so many miles until truck would be restricted to 65MPH. I took my truck into Kendall dealership in Nampa, Idaho and was told there was myself and another person who had the same issue. A couple weeks go by and I call the dealers…

Owner-reported narrative. Look up ODI 11459422 at NHTSA ↗

Problem: Unable to shift transmission from D to another position like R, P, N due to snow/slush being on shifter. I travel on Idaho state highways and County roads that are plowed. In February, I traveled state highway 14. Road conditions were plowed snow roads, broken snow floor, slush and pavement without slush or snow. I had a passenger with me on this trip from Elk City, Idaho to Grangeville, Idaho via SH-14. When I pulled into my storage unit, I could not shift from D to P or N or R. I could only drive forward. The temperature in Gra…

Owner-reported narrative. Look up ODI 11459426 at NHTSA ↗

The right rear tire (Goodyear Wrangler 275/65R20) separated and blew out on the highway, the truck was very difficult to control however it was safely stopped and there were no injuries. There was no observed warning prior to the blow out. The tire separation caused damage to the right rear quarter panel. The spare was installed and finished the trip safely. A tire shop found a second tire with evidence of separation on the left front corner. The tire that blew out on the highway is (DOT PJOT JB1V 0721) and the other 3 including the one wi…

Owner-reported narrative. Look up ODI 11523697 at NHTSA ↗

Reported: 2020-12-17 (December 17, 2020)

General Motors, LLC (GM) is recalling certain 2019-2021 Chevrolet Silverado 1500 and GMC Sierra 1500, 2021 Chevrolet Suburban and Tahoe and GMC Yukon XL and 2020-2021 Chevrolet Silverado 2500 and 3500 and GMC Sierra 2500 and 3500 vehicles. The seat belt brackets may not be secured to the seat frame in the front-row center seating position.

Consequence: If a seat-belt bracket is not secured, the seat belt may not properly restrain an occupant in the front-row center seat position, increasing the risk of injury in a crash.

Remedy: GM will notify owners, and dealers will inspect left-side and right-side front-row center seat-belt bracket attachments and reassemble it correctly as necessary, free of charge. The recall began January 26, 2021. Owners may contact GMC customer service at 1-800-462-8782, Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202314670.

Reported: 2020-12-23 (December 23, 2020)

General Motors, LLC (GM) is recalling certain 2020 Chevrolet Bolt EV and 2021 GMC Canyon and Sierra 1500, 2500 and 3500, Yukon, Yukon XL, Cadillac Escalade and Escalade ESV and Chevrolet Blazer, Camaro, Colorado, Equinox, Silverado 1500, 2500 and 3500, Suburban and Tahoe vehicles. Incorrect bolts may have been used at one or more fastening locations to secure the seat belts to the vehicle. If an incorrect bolt was used, the seat belt may not be properly attached to the vehicle.

Consequence: If a seat belt assembly is not properly attached to the vehicle, the seat belt may not properly restrain an occupant in the event of a crash, increasing the risk of injury.

Remedy: GM will notify owners, and dealers will replace the suspect bolts, free of charge. The recall began January 29, 2021. Owners may contact GMC customer service at 1-800-462-8785, Cadillac customer service at 1-800-458-8006, or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202322230.

Reported: 2021-09-29 (September 29, 2021)

General Motors, LLC (GM) is recalling certain 2021-2022 Chevrolet Silverado 2500, Silverado 3500, GMC Sierra 2500, and Sierra 3500 vehicles with electronic brake control modules (EBCM) replaced during vehicle assembly. The bolts that attach the brake pressure modulator valve (BPMV) assembly may not be properly tightened, which could fail to seal the two sub-assemblies and allow water intrusion.

Consequence: Water in the BPMV may cause an electrical short circuit and increase the risk of fire.

Remedy: Owners are advised to park outside and away from other structures until the recall repair is completed. Dealers will replace the BPMV assembly, free of charge. Owner notification letters were mailed on October 20, 2021. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-800-462-8782. GM's number for this recall is N212349181.

Reported: 2024-02-01 (February 1, 2024)

General Motors, LLC (GM) is recalling certain 2020-2024 Chevrolet Silverado 2500, 3500, GMC Sierra 2500 and 3500 vehicles equipped with power-unlatching tailgates. The tailgate's electronic gate-release switch may short circuit due to water intrusion, which can result in the tailgate inadvertently unlatching while the vehicle is in park.

Consequence: An unlatched tailgate may open while driving and result in a loss of unsecured cargo, creating a road hazard and increasing the risk of a crash.

Remedy: Owners are advised to check that the tailgate is closed and latched before driving. Dealers will replace the exterior touchpad switch assemblies, free of charge. Owner notification letters were mailed May 17, 2024. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-800-462-8782. GM's number for this recall is N232426400.

Reported: 2024-10-24 (October 24, 2024)

General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel engines. The transmission control valve may fail and cause the rear wheels to lock-up.

Consequence: Rear wheel lock-up can increase the risk of a crash.

Remedy: Dealers will install new transmission control module software, free of charge. GM will provide a special coverage program to cover the repair of transmissions that are identified by the remedy software as containing a defective control valve. Owner notification letters were mailed December 12, 2024. Owners may contact GM customer service at 1-888-988-7267, Cadillac customer service at 1-800-458-8006, GMC customer service at GMC 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N242454440.