Allison 3060 transmission help

[ml238]

Posting this thread for my brother-in-law. He is having trouble with his Diesel pusher with an Allison 3060 transmission (year is 93). Starts fine and engages into gear when cold. Can drive forever and transmission shifts smoothly with no problem. If he takes it out of gear it will not go back into gear until it cools off for a half hour or so. The selector will select but transmission (monitor) won't go into reverse or drive. So far he has replaced all the grounds he could find. I have seen on some other threads that it could be the ECU and some recommended a shop / person to rebuild for a reasonable price. Any guidance is appreciated. Thanks much Mark - upstate NY

 

[dbarton291]

Re: Allison 3060 transmission help

When (if it's got a selector with two digits) it's in neutral the selector should say N N. When he selects drive and it won't go, the selector should display D N. Is the N flashing, or do you see the selector displaying D D?

If it's got a selector with a single digit, is it flashing when it won't go into gear, and what letter is flashing?

 

[ml238]

Re: Allison 3060 transmission help

Dbarton - first thanks for offering advice. The selector has two digits. When in neutral is displays N N. When in drive and it won't go, the selector displays D N. When in reverse and it won't go it displays R N. We don't know if it flashes. I asked him to try to replicate the problem and let me know if it flashes.
Thanks again. Mark