35 inch actual milage

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I was wondering if when people upgraded their tires to 35s and checked the odometer/trip to get their calculated gas milage if they factored in the size difference?Because when I factor in the 11% difference I'm getting 1mpg better. Or is this just a crazy thought that makes no sense?
 
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whatever your currect gas mileage is with your 35s (if you havent fixed your speedo) yes you DO have to add back roughly 10% to the number of miles but like Doug said no way would it ever be better then stock..
 

e9999

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35/31=1.129 so +13% if those are the real dimensions (of course, they usually aren't)
 
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Larger, wider, heavier tires, less MPG. No exceptions. Pure placebo effect.

DougM

Counter point (not prepared to argue this though....)

It is a well known fact that companies install a higher final drive ratio to achieve better highway MPG. Sometimes this is done with overdrive, and sometimes with R&P ratios (or both.)

Changing from 31" tyres to 35" tyres effectively increases the final drive ratio by ~12% (higher ratio; lower numerically). As one would expect, the heavier tyres have more rolling resistance and more mass so it is unrealistic to expect a 12% improvement in fuel economy, but it is possible that one would see an overall MPG improvement at HWY speeds. N'est-ce pas?

-B-
 
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I was wondering if when people upgraded their tires to 35s and checked the odometer/trip to get their calculated gas milage if they factored in the size difference?Because when I factor in the 11% difference I'm getting 1mpg better. Or is this just a crazy thought that makes no sense?

Is this with or without 4.88's?

Would 4.88's make a difference in mpg?
 
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Is this with or without 4.88's?

Would 4.88's make a difference in mpg?


Its with stock gears and I've had made an effort to drive the freeways as much as possible so I can cruise at 2000 RPM in the slow lane. Another question, when you change the gear ratio from stock to 4.88, does that bring the odometer back to actual milage?
 

Romer

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Its with stock gears and I've had made an effort to drive the freeways as much as possible so I can cruise at 2000 RPM in the slow lane. Another question, when you change the gear ratio from stock to 4.88, does that bring the odometer back to actual milage?

Actually it take the odometer past stock and the speedometer shows you are going faster than you really are. I bought a Yellow Box speed corrector to adjust it back to stock.
 

MaddBaggins

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With 4.88's and 315's I used GPS and kept track on a long freeway trip and around town. I don't get anything significantly different than I did with stock gears and 285's.

average 12.5 around town (IF I keep my foot out of it)
about 14-15 freeway depending on the hills.
 
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Its with stock gears and I've had made an effort to drive the freeways as much as possible so I can cruise at 2000 RPM in the slow lane. Another question, when you change the gear ratio from stock to 4.88, does that bring the odometer back to actual milage?

With 35" tyres and stock gearing (4.10:1) the speedo/odo indicate slower than actual.

With 35" tyres and 4.56 gears, the speedo/old indicates actual (or very close)

With 35" tyres and 4.88 gears, the speedo/old indicates faster than actual.

You need a correction box (Yellow box like Ken suggested or TruSpeed or Marks from Slee.)

-B-
 
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With 35" tyres and stock gearing (4.10:1) the speedo/odo indicate slower than actual.

With 35" tyres and 4.56 gears, the speedo/old indicates actual (or very close)

With 35" tyres and 4.88 gears, the speedo/old indicates faster than actual.

You need a correction box (Yellow box like Ken suggested or TruSpeed or Marks from Slee.)

-B-
I'm aware of the speed correction boxes that you're talking about. I like the fact that my odometer reads slow because I'm a limited milage insurance plan and this helps me cheat alittle. ;)
 
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I got 20 mpg when I went to 35's. Part of my calculation involved making my kids get out and walk :flipoff2:
 

ginericLC

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Whatever.

Remember that you have to sign that odometer statement indicating that the mileage is correct when/if you ever sell the vehicle.

-B-

Not true, if the vehicle is more than 10 years old they are exempt from the mileage statement. Read the fine print on the title. After this year all 80s will be exempt on mileage.
 

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