General Motors has identified a defect in certain 2012-2013 Chevrolet Silverado and GMC Sierra chassis cab vehicles equipped with 6.6L diesel engines and dual fuel tanks. The safety defect was found as a result of an investigation into increased warranty claims of the fuel transfer pump.

The transfer pump, which moves fuel from the rear tank to the front tank, could malfunction due to a change in circuit board design and manufacturing process by the pump supplier. The problem could cause the fuel gauge to give inaccurate readings, illuminate the “Service Engine Soon” lamp, reduce engine power, prevent the vehicle from starting, or cause the engine to stall. Unexpected stalling of the vehicle could increase the drivers chance of an accident.

GM will notify customers, and dealers will inspect and replace the fuel transfer pump as necessary. GM will also issue a service parts bulletin (GM Number 13421) to recall any service parts sold after April 1, 2012, to inspect and replace the fuel transfer pump as necessary. Owners wanting more information about the problem can contact Chevrolet at 1-800-222-1020 and GMC at 1-800-462-8782. GM’s recall number is 13420 and the NHTSA Campaign Number is 13V-615.