Changing 4th gear shift point

[turbo_bu]

For a stock Allison is it acceptable to reprogram the TCM to make it shift into 4th gear sooner? All of the other gears will shift with the engine speed at or below 2000 RPM. For 4th gear, you have to get to ~38 MPH before it will shift with stock tuning (light throttle shift point). I know that the 4th gear is the weak one on an Allison, but was wanting to get into it sooner for better mileage in town. Or will this just cause more wear on the transmission?

 

[duramaxin14]

I beilve there is a way for u to do it but it may cause wear not to sure though. about the wear part but i do no u can make it shift sooner

 

[Mike L.]

I think you should leave it alone. If it were my trans I would cancel your warranty if you did this.

 

[dynarex]

tcc duty cycle

why is it set to 65%max?-what does it actually do and is there a benefit to making it higher?

 

[Turbotug]

I think you should leave it alone. If it were my trans I would cancel your warranty if you did this.

Are there negative effects to longevity that would make you feel this is necessary?

 

[turbo_bu]

I think you should leave it alone. If it were my trans I would cancel your warranty if you did this.

Mike,

Thanks for your opinion. I was afraid that this was done for a reason by the Allison guys originally. Unfortunately my tranny is still stock and it would probably really hurt it