Please Help Guys!!!

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.


New member
Aug 2, 2019
I have an Allison 1000 in my 2500hd that will not move in forward gears! It goes into gear and then kicks out as if it where kicking into neutral. It has reverse and I have 0 codes! It almost acts like the e brake is on but it isn't. I have cleaned and checked all the connections to the TCM and I have cleaned all the ground connections. I replaced all the hall-effect sensors and the NSBU! I also checked the harness for damage and still nothing! It will drive all day in reverse and I jacked it up in the rear and it shifted through all gears up and down flawlessly! Please any Allison techs on here can you help me with a solution to this issue! I Need my truck back on the road! Thank you all for any help you can offer!!!!
Sorry about your troubles!  I could start something by saying you shoulda bought a ______, but I won't!

What year truck?  How many miles?  What engine?

I can not help, but others may be able to suggest a solution.  Answer these questions to help them!
At a guess, one or more of the internal solenoids has failed. I would expect an Allison 1000 to go 150k-175k miles before that happened, but maybe it had a hard life?  You didn't mention year or mileage or whether the tranny has been well-cared for,

Latest posts

Members online

Forum statistics

Latest member
Top Bottom