Conejabelica

Yes

Correct it will be in the reverse gear . But does not move. weird part is if you turn off the truck and turn it back on you can go in reverse. the truck runs good . No issues with it till now . It has like 990000 its never had any odd noises. It was running good then like one day it just decided to start shifting weirdly. And now this

No codes on reader. We’ve already done that. No check engine light either

So Rpm’s started going crazy we had it parked for a couple days . Today we tried get it into gm but didn’t make it. You can drive it at a certain rpm but then it will go crazy and like just not go. Can’t be put into reverse when this happens. if you turn off the car and turn it back on it will run but then same thing happens. 2017 gmc sierra single cab . 5.3L 2x4