gear ratio

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Mar 14, 2011 | 10:38 PM

codyawise

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From: Chambersburg, PA

gear ratio

just curious thinkin bout puttin a lockin dif in my 97 f250 and i was wonderin how do i find out what my current gear ratio is?

Mar 14, 2011 | 11:07 PM

95powersmoker

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From: Ellensburg, WA

You either have 4.10's or 3.55's What are your rpms at 75mph?

Mar 14, 2011 | 11:20 PM

codyawise

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From: Chambersburg, PA

i cant recall im down at school and my trucks at home ill check er out this weekend i know its somewhere between 2 and 3 but cant remember what exactly

Mar 15, 2011 | 12:37 AM

97dieselnewb

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at 75 id say im at 22-300ish

also codyawise what size tires are you running

Mar 15, 2011 | 12:22 PM

codyawise

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From: Chambersburg, PA

285/75/16 all terrains right now

Mar 15, 2011 | 09:10 PM

OceanDiesel

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From: Norwalk, IA

There should be a tag on the cover bolts that states the gearing. If it's there, you may have to take a wire brush and clean it up.

Mar 15, 2011 | 09:14 PM

95powersmoker

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From: Ellensburg, WA

It will also say on your door tag.. Should have an axle code and then go here to figure out what it is...What is my Ford rear end ratio, do I have positraction - Drivetrain.com

I figured you were with the truck, that's why I asked about the rpms.

Mar 16, 2011 | 12:16 PM

codyawise

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From: Chambersburg, PA

yea unfortunately i dont have it til the weekend i just bring my beater car down to school. but yea i will definitely check it out when i am able. thanks for help.
also which would be better a posi or a lockin dif