Forrest Friedrich

My '21 Sierra 3.0, which is at 10k miles, gave me a message yesterday saying that the DEF tank was empty, and that I had 500 miles to fill it. But I knew that it was about 60% full. The message seemed to be elevation related, and went away when I got close to sea level. If I put a scanner on the OBD port the DEF level reads 60%, then 0 for several seconds, then 60%, then zero for several seconds. Gauge in the dash always reads correctly, unless it's telling me to refill immediately. Not looking forward to calling the dealer. Pretty sure I'll hear, "Gee, we've never heard of this problem before. Without a Check Engine Light there's not much we can do."

I picked up my Sierra out of state, had the no-start issue happen 3 times in the first thousand miles (about 3 days), both hot and cold starts. Once home I did two things. First I tightened the fuse block screws (they were way below the 53 in-lb threshold), and, second, I frequently put an AGM-specific battery charger/desulfator on the battery overnight. I've now had the truck for four months/6,500 miles, haven't had another no-start event. Do either of the things I did contribute to the fact that the truck has been fine since I got home? I have no idea, and evidently GM has no idea either. But I'm glad that it's working correctly, as it's an incredibly nice vehicle except for the starting issue. I tell people that if Lexus made a truck, this is what it would feel like.

Ok, here's one more 3.0 Duramax with the no-start problem; '21 Sierra 1500. It happened twice within the first two days of ownership, four times total to date. I've owned it six weeks, 2,600 miles on the clock. Always seems to happen after it's been run, then stopped for a few minutes, then an attempted re-start. Never on an auto-stop/start. I really hate the idea of having my new $60k truck being completely torn apart. I can't imagine that it would ever be quite as tight and quiet as it is now. Crap. I can't imagine how much GM is going to have to spend to fix this problem, if in fact the cabs have to be removed. I'd love to know how many problem vehicles have gone out the door.