32's and MPG
 

Well ive ben running these 32s for over a week now.. I checked my fuel mileage yesterday after i filled up...I have a 16.5 gl tank.. and 3.73s...The divison showed 271/14.5= 18.58 MPG....Thats the same as i have been getting?? I also checked out the ranger station's tire chart on RPMs and im in the Better fuel mileage range....In 5th gear at 65 im running 21-2200 RPM...Thats good right???
Someone tell me if i am making a mistake!

I may be wrong, but i think that chart says in 4th gear on a OD transmission, not 5th/OD

They're the same ratio.

Have you compensated your speedo for the bigger tires? If not, your odometer is actually reading fewer miles than you're traveling by about 10% or so. Your gas mileage may be even better than you think.

The tires themselves may be the difference: their rolling resistance may be significantly less than your old ones somehow.

Yeah you are right about being in 4th OD instead of 5th...UM no i havent calculated my speedo, its pretty snug...lol...NAH i really dont think its much of a difference, the next police clocker i see ill just cruise at the speed limit and check my MPH and then ill calculate doing that....Or is that a bad idea???

You say by 10% my mileage may be off? How does that compensate for the exact mileage i got before the tires then? help me out here

with my 97 i had 3.73s and put 4.10s with 31 buckshots and had a city cop clock me and my speedo was right on...which we both thought was odd

i use those "speed clockers" all the time. i just drive by, at the posted speed (say 30) when it tells me my speed, i check my speedo again. even with my 32's i'm always dead on. before, with the 31's i was always 3 mph slower than what the police clocker said. so, if my speedo read 30 mph, i was really doing 27mph. (when i had the 31's)