06 LBZ, recently built trans (about 3000 miles on it), but pan never came off as I installed a Transgo Jr about 100k ago with no problems. Spin on filter has been changed twice since build, along with more recently fluid and internal. Went to leave and trans freewheeled up to about 2000 rpm in drive. Quickly let off, put it in park and then back to drive and free wheeled again, then slammed into gear, got on brakes, then back to free wheel. Still had reverse and could move forward if put in first. Only once I parked it (didn't move more than 30 ft) did it throw a shift range inhibited. Checked codes and had the typical 0700 and 0701, along with 0848 and 0877. Fluid level is fine. It had done it once before however never through codes and after it caught it drove fine (this was about 300 miles ago with no hiccups in between).
Just trying to figure out where I should start looking instead of throwing out a shot in the dark with cleaning trim valves or replacing harness.
Just trying to figure out where I should start looking instead of throwing out a shot in the dark with cleaning trim valves or replacing harness.
