# Equivalent gear calculators?

Discussion in 'The Garage' started by sled_dog, Aug 2, 2006.

1. ### sled_dog1 ton status

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Anyone know a gear ratio calculator that will tell me what gears I need to run with a certain tire? Namely I know there are some that if I enter that I have "31s and 3.73s" it will tell me that if I run 35s I need "x.xx" gears to make it the same as what I have now. Anyone?

2. ### ryan22re1/2 ton status

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The equation looks like this:

old tire size/old gear ratio= New tire size/Equivalent gear ratio

going from 31-35's with the same 3.73's and a little algebra we get:

31/3.73 = 35/X

X = (3.73*31)/35

X = 3.30

3. ### ryan22re1/2 ton status

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Eh, now that I look at it, X should be 4.211, that's what you would need to get your ratio back to stock...

Should be X = (3.73*35)/31 = 4.21

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6. ### BigBen1/2 ton statusPremium Member

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