Today was the first day it really snowed and i was using my 4wd a lil bit today to keep from slidding all over the place. Well tonight when i got in my truck to head back home i started it and when i tried to shift it into drive i could feel it shift into it but the light on the console wasnt lit up. I figured something wasnt right so i tried shifting through all the gears. The ligh on the console would not come on in 2nd or park either. When i shift it from anything below drive (I.E. 3rd, 2nd, 1st) and then shift it back to park or reverse it makes a awfull noise and really jerks bad. I drove it around the block a lil bit and with it in drive it will shift into all the gears but takes a really long time to go from 3rd to 4th but after 4th it is fine. If i put it in 2nd and drive it, it will still shift into 3rd but not any farther. I drove it for a lil while with it in drive and after the initial part of it not wanting to shift into 4th everyhing is fine and the light on the dash eventually comes on. It still would shift really hard back to park or reverse. i checked the transmission fluid and it was a little low so i thought that might have something to do with it so i filled it up all the way to the top and still made no difference. There are no codes and i cannot figure out what is going on. this is scaring the crap out of me. i cant afford a new tranny. The truck only has 77k on it, would it stil be under warranty? God i hope so!!

Thank you guys for and help

Often this is the switch (NTBU?) on the side of the trans. Allison dealers have the best price. It is susceptible to the elements and failures are all too common.

If you were driving in 4wd on dry pavement your front and back tires need to be the same diamater or you will be loading the drivetrain because the larger one is traveling further than the smaller. Tire wear in and of itself can be sufficent if driven long enough on dry pavement(no slipping to compensate for size difference). I would drive it for awhile and forget it if it continues to shift OK but I would check the fluid level as you may have overfilled it if it wasn't hot when you checked it and topped it off. Foaming fluid will cause poor operation and possibly leaking out the vent. If you overfilled it you may be able to get it back to where it belongs by changing the filter without prefilling.

Sounds like the switch mcrat was talking about is at fault if you were missing some of your prndl display

Mine did the same thing and the dealer said it was the neutral safety switch or something like that. Probably the same thing Mcrat said it was, Its no big deal anyway.

went to a allison dealer today and picked up the NSBU switch. I was suprised at how cheap it was, i was expecting it to be alot more. Installing it was really a pain in the *** becasue it looks like the plugs in the original one were glued in. But anyhow i got it out and put the new one in and everything is working great. Thanks for the info guys, much appreciated

Good, glad you got it worked out.