Duramax Diesel Exhaust Fluid 2024. Checking the def fluid level is an essential. Enter your engine rpo (lb7, lly, lbz, lmm, lml, l5p) to see detailed fluid capacities and.

This is the first time i got a def message on the 2024, but i remember my 2020 would first come with a 1000 mile message. I got this message on my way to work this morning, it popped up with 500 miles def range.