48re Failure
 

2 weeks ago my 2006 4x4, 4 door, longbed was experiencing the shuttle shift syndrom (2-3-3-2-2-3) at light throttle, so I replaced the Governor solenoid, pressure sensor and installed a Trango shift kit. This corrected the shuttle shift, improved the shifts and improved the drivability of my rig.
Then about one week after this the truck suddenly goes into limp mode, starting from a dead stop in second or third gear and unable to even manually select first gear. The fuses have checked out good and I'm at loss on which way to go from here. Any sugestions.

Call Goerend they are very helpful and you may even get a trans!

easy peasey
 

drop your tranny pan and see if you have anything like this http://transmissioncenter.net/Power-Wedge.jpg or http://www.transmissioncenter.net/HPIM1224.JPG in there... if so check out PATC 46RE 47RE 48RE Transmissions, Performance Transmission A518, 518
they'll get you what you need..(probably a 2nd gear band) they helped me out fast and in a hurry and it isn't too hard to change any of this... just make sure you use a torque wrench!!! do it right and don't cut corners

I changed out mine and it started to do the very same thing. So I took the pan back off, and I had forgot to snap the little red plastic retainer clip in place that holds the solenoid (I think thats what it holds, been a long time ago), anyhow, it was fine for about 2 miles, and it started to do it again. Turns out I was about half a pint low on tranny fluid. Not sure if this is your problem or not, but I have not had an issue since. Hope ya get it figured out!

Update to my condition.
The transmission was dismantled and bits of torque converter clutch were clogging some important passages, a simple overhaul and I'm back on the road again