Rear Gear ?'s

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Feb 16, 2004 | 11:44 PM

good 'ol ford

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From: e-burg

does this sound right ??

i have a 77 ford f-150 it has a c6 tranny and at 70 it runs at about 32- 3500 rpm i wanted to get i higher gear ratio to lower that a little bit. i rolled under it the other day and the tag on it said that i had a 3.25 which just sounded way to high to me any one have any idea if thats right or how i could tell what it truly is thanx

Feb 16, 2004 | 11:56 PM

FordPickup460

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Joined: Nov 2003

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From: Cab of a truck

There are alot of ring and pinion websites that have a ratio calculator, they are fairly accurate. ringandpinion.com i think

Feb 17, 2004 | 04:44 AM

Jerrybo66

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Joined: Mar 2003

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From: AZ.

That's about what the rear my ''73 has. Your RPM's seem way too high for 70 MPH. Are you sure your tranny's not slipping?

Feb 17, 2004 | 05:43 AM

Torque1st

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Joined: Sep 2001

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As a general rule of thumb for a stock tranny about 5-10% slippage is normal. You can find more tranny info in the tranny forum.

Feb 17, 2004 | 07:29 AM

Icicle

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Joined: Mar 2003

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From: Spokane WA

A given gear ratios RPM at a certain speed will change with different tire sizes, here is a calculator where you can figure it all out yourself, good luck