Just picked up my truck with new 4.10's. My speedo is off about 10mph at 65. (if doing 65 actual speed, speedo reads 75).
I need to change the little gear to calibrate the speedo.
I thought the gear was int he tranny.
There is another post on here that says it is in the transfer case.
MY truck is a 97 with the 4.6L auto tranny.
Dirtyd0g...can you give me some help in how to change this gear? Whats involved? how hard is it? Do any major parts have to be removed (ie: drop transmission pan, valve body etc).
Please give me as much info on how to do this as you can. if it is easier for you please send me an email if it is a lengthy post.
Thank you

 

anyone?

 

The gear is very easy to change. Find the speedo cable, ( Look for a thick wire covered in hard black plastic that leads to the rear of the trans/front of t-case) The cable is held in by a 11mm bolt I believe. Once you pull the cable out, a small C clip holds it on from the end. Take the clip off and pull the gear off. If your speedo is reading fast you need more teeth, if it is slow you need less teeth. Hope this helps, let us know..

 

Dude, buy a Superlift "Truspeed" calibrator. It's about 100 bucks, it connects to some wires under the hood. It has a screw on it to adjust the signal your speedo recieves, reall easy and cheap - it works, get it

 

The speedo's on the '97s are analog and cannot be altered by microtuners. He will have to change the gear.