Kodiak TCM Reprogram

[stibuilder]

So there has been a lot of talk in the medium duty truck forum of the Allison 1000 in 06 coming with 6 internal gears but the TCM locking out 6th due to a bunch of things tire speed ratings,truck top speed etc. Some have been able to what they believe have the TCM reprogrammed at a local GM dealer with a Vin# from a newer 08 truck and the 6th gear is unlocked and they see about a 400 rpm lower cruising RPM drop.

So I did all this with my 07 Kodiak, had the dealer do the code update and then when a friend of mine with a V2 loaded up the TCM he could see 6th gear unlike before but when we commanded the transmission to go into 6th it went into Neutral instead, the gear selector indicator flashed and that was that. We even lowered the speed that it would shift into 6th still with no resolution.

My question is the transmission had an internal NSBU so we could only assume from the build dates it was built with 6th gear.

During my top end work I plan on using the transmission that came with the motor and its a year older but still in the range verified by Allison.

My question is should i use the TCM that matches the new transmission and have it reprogrammed by someone other than the dealer and does all this sound plausible?

Thanks!

 

[Stingpuller]

6 speed

I did mine but didn't like it. I ended up locking 6th out until 72 mph. I worked fine just didn't need 6th.

 

[stibuilder]

I did mine but didn't like it. I ended up locking 6th out until 72 mph. I worked fine just didn't need 6th.

This is exactly what we found with a friends Kodiak, he had 6th come on way to soon, before we did a road trip with my trailer it just didn't work well until 72ish. He was able to flip the trans lockout button quickly and lock it in 5th for some hills and that really helped.

How did you do yours?