Good morning everyone, I'm new to the group, I have a h3 hummer with a change problem, as soon as I leave everything is ok, when I exceed 20 miles the car goes up and turns but the gear does not enter. No noise and no spy. Who helps me please?

 

if your speedometer is not stuck permanently at that speed and it goes up without moving then you have broken axel or diffs.

 

Scan and post the codes!