2000 EB 4X4 Gear ratio change

[CLIFFORD2000]

I will be changing the gear ratio on my 2000 Eddie Bauer 4x4, 5.4 liter from the factory 3.55's to 4.10's and I have been searching the forums and can't find the answer to this question; Will the speedometer require recalibration? I am not changing the tire size. I cannot find a consistent answer as to which sensor controls the speedometer, the rear differential sensor or transmission sensor. Thanks for any help on this.

 

[Yupster Dog]

Watching this thread.

I have a 02 EB and Ford changed from 16" tires to 17" in that year.
My speedometer has always been off 10 MPH. (If you are going 35 it reads as 25 on the dash)
The milage is spot on.
I always figured that the truck was built for 16's and got 17's instead.
So, I am defiantly interested if it's an easy fix.

 

[Expd830]

I now have the same question. I have ‘02 EB stock 17” tires and was wondering what gear I would need if going 37” tires. And then would I obviously need to tune afterwards?

 

[Dimz]

There was a device at one time that cost 150$ in the mid 2000s but its no longer available. It also required changing a small plastic gear on the odometer cable. I would not mess with it. Just reprogram your brain. :/) You just have to live with it. 3.55 v 4.10 is not a drastic change. If you upsize the tires from say 265 70 16 to like 285 75 16 it would level out, but then you need to lift it a bit so it don't rub. Its easy compared to a regear! Here is a pic of my front diff with 4.56 and an ARB locker in it.