Duramax Fourth Generation: 2007.5-2010 (LMM)
I got a LMM that's stumping me a little
Customer bought truck last summer, bone stock, 1 elderly owner, 105,000 miles. Truck is spotless.
It would randomly reset filter life to 0, and once and a while would get a low rail code. He brought truck to me and I drive it for a week and couldn't...