I just put on 285x75 r16 tires on my 99 F-150. After driving on the highway and comparing my odemeter to the mile marker signs I have determined that my odometer is a little bit under 10% low. Probably 8%. I assume the speedometer and odometer are measured from the same sensors. My question is are they mechanical or electronic? And how can they be adjusted?

 

https://www.ford-trucks.com/forums/s....php?&t=420475

 

THey are electronic, a Ford dealer can reprgram it for you with the WDS scan tool, or maybe an aftermarket reprogrammer. Dealer will prolly charge about .5-1.0 hour, or 35-70 bucks.

 

Here is another solution. www.bluegauges.com/prod_yellow_box.htm - 17k

 

Or you can use a tuner like the DiabloSport Predator.

 

Thanks fella's for the info. I wish there was a way it could be done without alot of expense. Will have to call up ford dealer to see. I'll just live with it for now. If its an electronic spedo would the sender be compatable with aftermarket electronic spedo's like from jegs or summitracing? I want to add a tach to my setup to since my truck doesnt have one. Never tried to hook a tach to a dis system though. Not sure how to do it.