Technical Service Bulletin N222359341 — 2022 CHEVROLET SILVERADO 6500

Population expansion for emission recall. Certain vehicles with a 6.6L diesel engine. In cold ambient temperatures when Diesel Emissions Fluid (DEF) in the DEF tank is frozen, the DEF tank pump may be activated before DEF has been sufficiently thawed by the heater. If this condition occurs, the control system may detect no DEF flow through the pump, set a Diagnostic Trouble Code (DTC), disable DEF dosing for the remainder of the drive cycle and alert the driver of an impending reduction in maximum vehicle speed. Dealers are to reprogram the ECM.