Transmission getting stuck in 2nd gear

[berteras]

I have a 2008 NNBS Z-71, Roughly a month ago my truck got stuck in 4wd lo. I was about 10 miles from home so I drove it home, the next day I went through the motions and narrowed it down to the actuator or switch, since the switch was $30 I picked one up and changed it....it worked so problem solved so I thought. A week after that it got stuck in 4 lo again, I just left it alone and when I came back to the truck a few hours later, I started the truck and switched it out with no problem. Ever since then, it's getting stuck in 2nd gear. What it's doing is while slowing down it will get down to 10-12 mph than the speedometer will just go to zero and if I try to accelerate it will stay at 0 and it will not come out of 2nd gear. When this happens I have to either come to a complete stop or put it in neutral and tach it out than switch back to drive and than it's fine. It seems to be an electrical issue more than a mechanical issue but I have no idea what I could be! For what it's worth the truck does have a blackbear tune on it. Has anyone had this issue or know anything about this? Any info is much appreciated

[gmtech4]

Disconnect the tune and try again

[berteras]

I can't, I had the tune done in person.

[gmtech4]

Without looking it up on another devise I can tell you that when both shift solenoid are off (power failure) it will be in a gear , so if power IS lost ya can drive it ,

 

I feel you can do nothing on your own unless you have a scanner, service info and some mechanical repair background ,

 

Please let us know what you find cuzzzz no one does