02 Allison--Changing tires.

f7_ditch_jumper · June 25, 2003

I wanted to by a predator or a hypertech to reprogram the speedo on my truck if i change the tire size. I know the hypertech wont work but will the predator? I KNOW alot of you guys are running 285s or 265's, what did you do? Has any one tried taking it to an allison trans shop to have it done? This is really bugging me.

Professor · June 25, 2003

The Duramax Guys on thedieselpage are reporting success changing the speedo with the predator. Worked with my 6.0 and 4L80E as well. You can change the shift points on the 4L80E but not the allison.

f7_ditch_jumper · June 25, 2003

I took your hint and contacted Predator.

My Question:

I currently own a 2002 Silverado with 8.1L and an Allison Transmission. The main purpose of my purchase would be to calibrate my speedometer for bigger tires. I realize that the Preadator can not change the transmission parameters. What exactly is considered a transmission parameter?

The answer:

Transmission parameters include shift speed, firmness and rev/mph shift points. You will be able to adjust for tire size.

Good news for me.