Allison 5sp: Shift indicator problem

[duramax3388]

The shift indicator in the dash will only show up when its in park reverse and first. If its in any other gear it will not highlight it to tell what gear its in. Its a buddies truck and its been a really long time since i have had to mess with a ally

 

[Mike L.]

Possibly a bad NSBU.

 

[duramax3388]

thanks mike thats was the first thing i said to him of the top of my head but wanted to make sure. Is there any way to check with efi live or anything or is it just a change it and find out deal

 

[Mike L.]

thanks mike thats was the first thing i said to him of the top of my head but wanted to make sure. Is there any way to check with efi live or anything or is it just a change it and find out deal

It's cheaper to replace it than spend the time to diagnose it. Just make sure you install it correctly.