Allison HD4000MH Wiring Project

[sojourner58]

I've been posting on this forum for several years, mostly about my 1982 Model 10 I purchased with a low mileage 500 HP Cummins N-14 engine and an Allison HT740 transmission.  To recap, I purchased it several years ago from a seller in WA and drove it home to OH.  The HT740 transmission overheated and started slipping on the way home.  I lost reverse gear completely but made it home without having to be towed.  A couple of years ago I finally got around to dropping the pan on the HT740 and found steel debris so I knew it wasn't salvageable without a major rebuild.  I spent last summer removing the HT740, installing another flywheel housing, fabricating new engine mounts and installing an HD4000MH transmission.  The shop where I had been working on it wanted their space back to work on other trucks and they weren't interested in wiring the new transmission so I flat towed the coach to my shop a few miles away and it's been sitting there ever since. 

I have factory Allison manuals with schematics, a touch pad shift control, a transmission control module and a wiring harness from another coach.  Life has been getting in the way of me completing the wiring for the new transmission.  I was hoping to find someone other than the local Allison service garage, Western Branch Diesel to help with the wiring.  I've had bad experiences with their service and parts departments.  If I could find an independent Allison technician who would be interested in tackling the project it would be a great help.  I can probably do it all myself but my schedule has been preventing me from doing so.  

If anyone can recommend someone around the NE Ohio area that might be interested I would appreciate it immensely!

[beltguy]

I was hoping you might get some direction from a person of experience.  That is not me, but that never stops me from jumping in.

From your description, it sounds like you have the full harness to run from back to front.  That is a huge deal, as making harnesses is not a fun job. 
Further, I hope the harness is terminated with ends that can either be connected directly or are of help defining the wires.  If it does not have terminations, I hope the wires are labeled.

I suspect the Cummins will need to be re-programmed so that it can talk to the Allison.  Not sure if the Allison will have to have some software adjustments.  Finding a person with a computer with Cummins and Allison software might be a bit of a challenge.

Depending on your rear end gearing, you may have to have the sixth gear activated. 

You will love the gearing that will reduce your cruising RPM to better fit the Cummins application.

In lieu of an Allison dealer, you might try to find a mechanic from the school bus system that would like to earn some extra money. 

Keep us updated.

Jim