Gear ratio change

[TD-5]

If I do a gear change from 3.55 to 4.10 or 4.30, how does the ECM know the new gear ratio?
Is there a base parameter that is accessible thru IDS or similar programming to change this, & then do the fine tuning with tire size?
Or is it all done thru the tire size parameter?

 

[Jonnydime]

The speed sensor reads a tone ring on the ring gear. It does not matter what gears you have it will read the same.

 

[Jonnydime]

Tire size is the only thing the changes the speed readout.

 

[TD-5]

Well I'll be Dammed, I never thought of that, thought it was only for ABS & Traction control. Thank you for the feed back.

 

[Highroller54]

I'm going from 3.55 to 4.10 to, I'm on 37's and hate my gears.