GM is recalling seven different truck models spread across three years. The recall affects the 2017-2019 Chevrolet Silverado 2500HD, 2017-2019 Silverado 3500HD, 2019 Silverado 4500HD, 2019 Silverado 5500HD, and 2019 Silverado 6500HD, plus the 2017-2019 GMC Sierra 2500HD and 2017-2019 Sierra 3500HD. Specifically, it includes these models with the 6.6-liter Duramax diesel engines and the optional engine block heater.
The recall technically deals not with the engine block heater itself, but the way it is connected. According to NHTSA campaign No. 19V328000, the engine block heater cord or the terminals that link the cord to the heater could short circuit. A short circuit could potentially damage engine components and result in a fire. According to The Detroit News, 19 fires have been reported but nobody has been injured.
GM has yet to figure out a fix, and thus has not yet released a notification schedule for affected customers. If you believe your vehicle is part of the recall, contact GM customer service at 1-586-596-1733 and use reference number N182206310.