Equipment: electrical: engine block heater (Chevrolet and GMC)
Vehicle recall 21V-496. NHTSA received General Motors, LLC’s report on Jul 1, 2021.
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The short answer
NHTSA received General Motors, LLC’s report on Jul 1, 2021. Copied from NHTSA on Oct 19, 2026.
Every line below is in NHTSA’s own words, with its source beside it.
What’s wrong with it?
An electrical short-circuit can increase the risk of a fire.
General Motors, LLC (GM) is recalling certain 2017-2019 Chevrolet Silverado 2500, 3500 and 2017-2019 GMC Sierra 2500 and 3500 vehicles equipped with a Duramax diesel 6.6 liter engine and an optional engine-block heater cord.
An electrical short-circuit may occur in the engine-block heater cable or in the terminals that connect the heater cable to the block heater.
NHTSA, Recalls flat file. Released Oct 19, 2026. Updated daily.
- NHTSA’s part: Equipment: electrical: engine block heater.
What should you do?
Dealers will replace engine block heaters and heater cords. Vehicles that have this feature disabled as a remedy to the safety condition will be contacted and offered replacement block heaters and heater cords under a separate customer satisfaction program, free of charge. GM will provide free replacement block heaters and cords under a separate customer satisfaction campaign. For vehicles previously included in recall 19V-328, the heater cord will be replaced and rerouted, free of charge. Interim owner notifications were mailed on August 13, 2021. Owner notification letters are expected to be mailed on April 4, 2022. Customers may call GMC customer service at 1-800-462-8782. GM’s number for this recall is 212329840.
NHTSA, Recalls flat file. Released Oct 19, 2026. Updated daily.
- How to reach the firm: Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.
- Check a vehicle by its VIN at NHTSA: the recalls still open on it are listed there.
Which ones are recalled?
NHTSA counts 338,020 vehicles potentially involved, across everything this recall names.
Each model year opens its own page: every recall naming it, its owner complaints and its crash ratings.
NHTSA, Recalls flat file. Released Oct 19, 2026. Updated daily.
Who is recalling it?
- Made by General Motors, LLC.
NHTSA, Recalls flat file. Released Oct 19, 2026. Updated daily.
What the record doesn’t say
- NHTSA’s recall file doesn’t say whether anyone was hurt. Owners’ complaints are counted on each vehicle’s page.
- Whether one vehicle or seat has been fixed: only its maker, or NHTSA’s lookup with a VIN, can say.
- How many have been returned or fixed isn’t in the notice.
Hearth Record wrote these lines.
Sources
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National Highway Traffic Safety Administration, Recalls flat file (FLAT_RCL_POST_2010).
Released Oct 19, 2026 and checked Oct 19, 2026. Updated daily. Public domain (U.S. Government work).
Vehicle, car seat, tire and vehicle equipment recalls, owner complaints and crash ratings are from the National Highway Traffic Safety Administration (NHTSA). Copied on Oct 19, 2026.