I've tried doing searches to find my answer but either I'm not smart enough or just that computer illiterate.

My question is there a way to change the speedometer with the computer so that a tire size change will read with in reason to being right?



1998 F-150 4X4(later 97 manufacturing)

 

if its mechanical you need a different teeth count on the gear, if it's electrical, the only way is with a tuner for these trucks... To my knowledge at least

 

Try calling an off road shop that does suspension lifts. They'll probably have some answers and could probably do it for you. One of my local Dodge dealers owns an off road shop right next to it and they take brand spanking new Jeeps and Rams and do lifts with bigger tires all the time and then sell them as brand new vehicles on their showroom. I would think their speedometers are accurate so I have a feeling it's something that can be done by computer.

 

In 97 you have to change the mechanical gear.

 

you'd be assuming they do that... Not all dealerships are honest or care enough to fix that small detail

 

Either way, I have a feeling that a shop that does suspension lifts and puts bigger tires on trucks day in and day out for a living would have an answer for this question as Im sure it comes up now and then.

 

they'd have the answers but I already gave answers for both solutions. Not hard to research if you have a manual or electronic, then go from there. Either buy a new teeth gear (for lack of a better term) or buy a tuner.

 

Yeah, fair enough.

How much do tuners like that usually run? Ive never bought one so I dont know but would it be cheaper to let a shop calibrate the speedo for ya (if your's can be changed electronically) or is the type of tuner youd need not that pricey?

 

97-98 have to have the transmission speedocable gear changed to facilitate speedometer mileage changes. 99 and up have electronic speedometers and can be programmed for the correct speeds with a tuner. This is the only way it can be done.

 

You need to change the speedo gear on the driver side of your transmission. Give me your old tire size and new tire size and I will let you know what tooth gear you need.