i have a 02 lb7. i busted a hole in the transfer caes. didnt loose much oil. fixed the whole not my truck will hardly shift at all. i have gotten a code reader on it and get these codes. p0500, p0700,p0722,p0841,p0848,p0875. i know what a few are but not all. it is my service truck so it is used daily and has a utility bed and weighs about 12000 will everything. i need help getting it back on the road.


ok so i answered my own question on the codes. but i dont have a clue how to fix them or where to start. please help me?

There is a guy Mike L that is the allison guy here. Search for him and PM private message him. Sounds like an issue a buddy had. But dealer took care of it. Was simply but may not be the same for you. transfer case typical pump rub. a few fixes for it. If you replaced the transfer case then did you do the pump rub fix? If not look at doing that or you may be in the same spot in the future. Check with Eric at Merchant Automotive for his pump rub fix kit. My thought is the NBSU switch on the transmission. Maybe you did not get everything plugged back in if you unplug connectors under there doing transfer kit fix. Might recheck all plugs and cables under there. Hopefully Mike L will see this and if not search for him.

Brian

we did not unplug anything from the tranny or from the TC. what is the nsbu switch?

Have a scanner put on and read the output speed sensor signal.

Yes as Mike says a scanner that read the output speed sensor. Like GM tech II or EFILive Flashscan. Or Dashhawk II. Not sure if Edge Insight can read that PID. NBSU is the Neutral Safety Switch.

Brian

Took it to Chevy to get scanned. Had 13 codes all for tranny and speed sensors. cleared codes and it worked great! thank for all the help.

Sounds good. probably did not get a list of the codes.

Brian

nope i didnt. i can call tomorrow and see. there was 13 of them. i will see if he printed it out!