Technical Service Bulletin 17067 — 2015 GMC SIERRA DENALI

17067 - Product Emissions Recall. General Motors has decided to conduct a Voluntary Emission Recall on certain vehicles equipped with a 6.6L diesel (LML) engine and dual fuel tanks (N2N). Under certain driving conditions, fuel may not be transferred from the rear fuel tank to the front fuel tank at a sufficient rate. If this occurs, the diagnostic trouble code (DTC) P2636 will set, the malfunction indicator lamp will illuminate, the fuel gauge will display empty, and the transfer pump will be disabled until serviced. If the vehicle continues to be driven, it will run out of fuel in the front tank and stall. Dealers are to replace fuel line connections to allow the rear tank, in addition to the front tank, to directly supply fuel to the engine. The engine control module (ECM) will also be reprogrammed with calibrations necessary to support this new connection.