Starting in 2011, Ford and General Motors began using Bosch Mobility CP4 pumps to provide high pressure fuel to their diesel engines. GM used the pump on its 6.6-liter LGH and LML Duramax diesel ...

It sounds like it could be the fuel supply; check the fuel filter, fuel pressure, and the injectors. It’s a common-rail diesel engine and they are prone to injector wear. Any diesel engine can be a ...