If you spin your tire one full revolution it will spin the driveshaft a hair over 4 revolutions for 4.10 gears, or about 3.5 times for 3.55 gears... no if ands or buts about it.


If you have a newer truck (98 and newer I believe), it will have a tone ring on the ring gear that the VSS on the differential reads. Hence, when you change gears, the tone ring still spins at the same speed the tire is turning even if you change gears, but if you change tires sizes it will throw it off and the computer will need to be re-calibrated. Make sense?

 

Will i spined the tire around one time put a mark and spun it around i layed under it and i tell you it only spun one and a half. But i have a 97 so how will i corect it and when i put the 35s on its still the speedometer is correct and i didnt change any thing

 

Make a bigger make so you can see it. Don't you know your number 1,2,4,5,6.......?

 

Lol yes i do i used a bright yellow marker and did it a couple times but i just took it for a drive and adn i think i firgured it out though the calc and i think i have 3.90s almost postive i do becasue those numbers are right on with the rpms i write down. So now i dont know if i want to waste money to swich to 4.11s or 4.56s

 

Ok had to check I saw the slowram. Didn't know which kinda of slow you were talking about.