speedo

[firefooll]

my speedo is reeding 70mph my actual speed is 65. not it is this way all the way through. so at 40 i am going 35. can this be change ny programming of do i have to change out the gear?

[Raul@Stealth Automotive]

Originally Posted by firefooll

my speedo is reeding 70mph my actual speed is 65. not it is this way all the way through. so at 40 i am going 35. can this be change ny programming of do i have to change out the gear?

do you have larger tires or a diff set of gears than stock? this can be done with programming... or a modual like the super lift true speed....

[firefooll]

just bought it i will check on it Friday its in the shop. odds & ends at the dealership

Cost 1 arm 4 toes of 1 kidney LOL:

[silverF250]

My speedo was off three miles an hour with 265's when I bought it put 285's on and it is back to normal.

[wes]

If it's a difference due to smaller tires. The speed at 40 would be proportionate not a direct subtraction. So if you are really traveling at 65 and it reads 70, when reading 40 you should be traveling 37. You are traveling about 93% slower than your speedo is reading. 65 is 93% of 70 just as 37 is 93% of 40.

[silverF250]

Well mine read three miles off at any speed and when I put on new tires it is correct now I have a garmin so i can check my speed while driving.

[wes]

that's ineresting. I have no idea then. The only experience I have with that is on my 94 f150 I read 65 when I am going 75 because of the 35"x12.50" 15"'s that I have on it and the difference is less the slower I go. Maybe the speedo sender is in a different spot. On the 94 its a magnet that reads a sproket in the rear end. I have no idea where the speedo sender is on psd's