gas mileage isnt as bad as you think.
#1
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gas mileage isnt as bad as you think.
Seeing it more and more. Had to make this post and lets spread this info around. Everyone says oh my mileage is so low with xx tire size. Chances are its not bad at all. If you dont know the exact miles driven everywhere you go with larger then stock tires or have a matched speedo gear for your tires your not even close to right with mpg calculations. 32" tires or less should only effect mileage by 1-3 mpgs. They are heavier.
31" your odometer is off 18% thats 51 miles off every 300 you drive
32" is off 22% thats 66 every 300.
Bigger the tire the more its off. However 33" and up the tires do get heavier and will have more actual effect on mpgs.
So lets stop telling people theyll get 10 mpg with 31" tires, etc. I get 17.5 mpg with mine and thats about 75% highway. Just got to know how to figure it out.
31" your odometer is off 18% thats 51 miles off every 300 you drive
32" is off 22% thats 66 every 300.
Bigger the tire the more its off. However 33" and up the tires do get heavier and will have more actual effect on mpgs.
So lets stop telling people theyll get 10 mpg with 31" tires, etc. I get 17.5 mpg with mine and thats about 75% highway. Just got to know how to figure it out.
#4
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Year: 89
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Originally Posted by bnkk
Thats why i listed percentages. The faster you go channges the amount your off but not the percent.
#7
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Year: 1998
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How would I sync it up correctly so it's reading it right? or am I just always going to have to add 60 miles to a full tank?
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Year: 1999
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okay do the math on this one.
I'm running 33's, stock 3.55's
my last tank from topped off to low fuel light I got 165.4 miles. I topped it off, it took 15.47 gallons. based off indicated mileage only it averaged 10.69 MPG. what is reality?
I'm running 33's, stock 3.55's
my last tank from topped off to low fuel light I got 165.4 miles. I topped it off, it took 15.47 gallons. based off indicated mileage only it averaged 10.69 MPG. what is reality?
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where did u get 18% from? I keep trying to find some info on this posted somewhere else other than on a forum. With my calculations ( i only went by the percentage of how much bigger the tire were from stock) I got 11.3% with 31's
Last edited by Lostfisher1; 03-12-2012 at 11:49 AM.
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Year: 1990
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Engine: 4 liter
So I am running 31's and using GPS police radar and running a course that the exact milage is know I came out with 10% difference on my Odometer so 10-11.3% is probably pretty acurate for 31s
#12
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Year: 1999
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Use this calculator to find the difference in tire size. http://www.google.com/url?sa=t&rct=j...08iM8nnZeMaGvA You want to look at the speedometer difference, NOT the diameter difference in red. The circumference of 31's are 9.5% larger, 33's are 15% larger, 35's are 23.9% larger.
Yay math! So with 33's you got 165.4 indicated miles, multiply that by 115% to get your actual miles. 165.4x1.15=190.2. So 190.2 miles/15.47 gal = 12.29 MPG. Still pretty bad but not as bad as you thought.
Yay math! So with 33's you got 165.4 indicated miles, multiply that by 115% to get your actual miles. 165.4x1.15=190.2. So 190.2 miles/15.47 gal = 12.29 MPG. Still pretty bad but not as bad as you thought.
Last edited by Cateyerr; 03-12-2012 at 03:58 PM.
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Year: 1999
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So the tire diameter is 15" + (6.64"x2) = 28.28".
So 31's are 2.72" larger. 2.72" divided by 28.28" = 9.6% larger than stock. Or you can just use the calculator I posted above
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Year: 1999
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Use this calculator to find the difference in tire size. http://www.google.com/url?sa=t&rct=j...08iM8nnZeMaGvA You want to look at the speedometer difference, NOT the diameter difference in red. The circumference of 31's are 9.5% larger, 33's are 15% larger, 35's are 23.9% larger.
Yay math! So with 33's you got 165.4 indicated miles, multiply that by 115% to get your actual miles. 165.4x1.15=190.2. So 190.2 miles/15.47 gal = 12.29 MPG. Still pretty bad but not as bad as you thought.
Yay math! So with 33's you got 165.4 indicated miles, multiply that by 115% to get your actual miles. 165.4x1.15=190.2. So 190.2 miles/15.47 gal = 12.29 MPG. Still pretty bad but not as bad as you thought.
#15
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i used a calculator i found that gave me those numbers from a yahoo search. im not sure how it does it but i know my work route is 66 miles a day and it calculated really close to the mileage i was reading on the dash. it could be wrong but nothing online is ever wrong