I got the 17 inch offroad tires(aftermarket). MY truck came with a 3.55 gear ratio and when I got it I made them put 32 inch tires on it. I know my speed is messed up what what about the odometer? Does is it reading to high? (more miles than i really have) or too low? (fewer miles than i really have) thanks


------------------
'97 F-150 XLT Expidition front end (no idea why). 17inch 4x4 wheels with 32 inch tires flowmasters with tips, K&N filter, 5-spd, 4.2 V-6 bedliner, bright clearcoat red, stepside, hidden hitch, 3.55 gear ratio, tinted windows and a BIG reg ford sticker on the back window (my greatest joy is cutting people off who have calvin pissin on the ford sign and they HAVE to look at my big red sticker)

 

If your tires are taller than stock your speedometer and odo will read slower than actual speed and distance. The bigger tire has a larger radius so it goes a longer distance per rotation than your system is calibrated for.

 

hey that'll work, when i go 60 i always feel like im going faster.

------------------
'97 F-150 XLT Clearcoat Red
4x2
4x4 wheels
Stepside, K&N, bedliner
32inch tires,flowmaster
tint, matching ford sticker
5spd fully loaded, hidden hitch
Comming soon:
spark plugs/wires,leveling kit,toolbox,
bed rails,push bar, CB with whiplash,
clear corner lenses,brush guard, blackouts,
edlebrock shocks, hypertech, K&N induction system,KC highlighters,
bed xtender, BOSE audio or infinity gold, disc changer,
side steps, dixie horn, white faaced gauges, and those small fender flares some 4x4's have,
matching boddy color of course, and some of those door guards,ventshade visors, power pulleys, that is all
i can think of right now

 

Yep, I have the same problem for now. I went to the 305s from the 255s and my speedo is off 5mph and my odo is off .1 mile. I'll eventually get it fixed.

 

Here is a link for you:
http://members.home.net/mjbobbitt/f150/tirecalc.html