Allison 5sp: U1024

LB7Diesel

Oh Boy!
Sep 3, 2006
1,355
0
0
Melbourne, F.L.
I've had a problem 3 times now with my trans reving really high and then slamming into 3rd. I finally pulled the codes and the only one I got was U1024 ( loss communication with tcm). Any ideas? Ground, nsbu, tcm?
 

Mike L.

Got Sheep?
Staff member
Vendor/Sponsor
Aug 12, 2006
15,686
232
63
Fullerton CA
Quckest was to diagnose a bad TCM is put a known good one in. Af that doesn't do it start checking connections at TCM. I have wiring diagrams if you need them.
 

LB7Diesel

Oh Boy!
Sep 3, 2006
1,355
0
0
Melbourne, F.L.
Thanks Mike! It's done this in a span of prob 6-8months. Hasn't happened in quite awile. It's the random sh!t that drives me crazy, and hard to track down.