Have a 2021 at4 3.0 Duramax with roughly 16,000 miles.
Just got a check engine light and message to service emission systems. Long story short, we had put expired DEF in and now it’s throwing codes.
Dealer won’t work on it under warranty so now i need to flush the DEF. Fortunately, the tech from GMC noted that the tank, pump and def injector had not been damaged and still operated as expected.
I can’t seem to find any guide or information on how to drain the fluid without removing the DEF tank. Is this even possible?
Maybe i could disconnect the main def filler hose and siphon the fluid out from the filler neck on the def tank??
Just got a check engine light and message to service emission systems. Long story short, we had put expired DEF in and now it’s throwing codes.
Dealer won’t work on it under warranty so now i need to flush the DEF. Fortunately, the tech from GMC noted that the tank, pump and def injector had not been damaged and still operated as expected.
I can’t seem to find any guide or information on how to drain the fluid without removing the DEF tank. Is this even possible?
Maybe i could disconnect the main def filler hose and siphon the fluid out from the filler neck on the def tank??
