Gas Recirculation Valve (egr Valve) problems of the 2011 GMC Sierra 2500

The contact owns a 2011 GMC Sierra 2500. While driving various speeds, the vehicle stalled and the check engine and exhaust gas recirculation warning indicators illuminated. The vehicle was taken to an independent mechanic where it was diagnosed that the fuel filter needed to be replaced. The vehicle was repaired; however, the failure persisted. The vehicle was taken to ranz motor CO (1401 w beech st, chanute, KS 66720) where the fuel filter housing and high pressure fuel pump were replaced, but the failure recurred. The vehicle was taken to another independent mechanic where they informed the contact that the fuel injectors needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failures. The approximate failure mileage was 220,000.

My 2011 GMC duramax displays codes (p0676), (p2493), (p122d0 and (p140a) related to the egr and throttle body. I located special warranty work #14353. I am told by gm customer care that my particular VIN is not included in the duramax diesel warranty issue. I located the following: 02/03/17nhtsa 10090458 TSB 14353 14353 - special coverage. On some vehicles, the service engine soon light may illuminate due to an inoperative exhaust gas recirculation (egr) cooler bypass valve. Dealers are to replace the egr cooler bypass valve. Where do I stand in getting general motors to honor the warranty?.