A while back I saw someone posted in a thread how to calculate fuel mileage w/ oversized tires.

I did a couple searches but couldn't find it. Could someone post it up for me, thanks.

 

I dont think you can do that.

 

figure out the fuel mileage
divide your new tire size by the stock tire size like i have 35s and 31s were stock, so my number is 1.129xxxx

then multiply those 2 numbers together

 

Yea I cant do that! lol

 

puff puff pass man lol

 

you gotta figure out the difference in circumference not the difference in diamter.

 

im 99.9% sure the pi and **** cancles out

there was a big argument in another thread a while back

 

ok thats a valid point, but circumference = pi x r^2
so you still gotta square the radius of the tire.

 

What are the stock and currant sizes of your tires?

 

its in the door jam of your truck. it varies

 

yea both are being squared.. can't that be cancled out too?

 

If you do that you might sacrificing the ride quality

 

Sounds like muffler bearings to me...

 

lol nice

 

circumference is 2 x pi x radius, the AREA is pi x r^2

 

99ranger4x4 is right.

 

dude, you cant "caluculate" your gas mileage with a tire based on size alone. there are a lot of other factors.

 

True, rotating mass and tire width have a bit to do with it, just to name a couple.

 

yeah all those, not to mention friction from tread design, compound duro, wheel weight, wheel size, offset, and thats just in the wheels...

 

Get a programmer. Adjust for the new tires. Fill up tank. Hit the trip button to 0. Drive till gas light. Refill, take gallons put in tank till its filled back up. Then take the mileage on the trip. Divide that by the amount of gallons and bam. You have MPG that is atleast 95% correct.

 

you guys are all wrong, heres what you do, when your filling up next time, just look at how much its costing you and cry.

 

THREAD WINNAAAAR!

 

Don't know why you guys are making this so complicated. MPG is an easy formula.
Miles driven, divided by, number of gallons used, equals miles per gallon.
With over size (or under size) tires, you have to adjust for the difference in size.
You can get a tuner corrected for the current set up.
Or you can find out how far off your speedometer/odometer is
by checking it against the mile markers on the side of most highways. Then adjust.
For instance if your odometer is 10% slow. (odometer says you have traveled 10 miles
and the mile markers say you've gone 11)
All you have to do then is add 10% to the "indicated" miles traveled to get true miles traveled.
If the odometer is fast, subtract the proper amount. Then divide by the number of gallons used.

 

either way it all still cancles out

i know, except for whats mentioned later in the thread, it also has to do with tread pattern and and fun stuff

 

Yeah put your way will give you approximate mileage.