Need Help With Gear Selection!

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Jan 24, 2007 | 11:27 PM

WATTSUP!

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Need Help With Gear Selection!

I Have An 89 F150 With A 300 Straight 6 With A 5 Speed. I Am Currently Running 36 Iroks With 9 Inches Of Lift. My Question Is What Size Gears Should I Go With? Right Now I Am Running 3.08's. Any Help Will Be Greatly Appreciated. Thanks In Advance!

Jan 25, 2007 | 01:21 AM

'88_F-150

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Joined: Feb 2005

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From: Pittstown NJ

i would go with at least 4.10's for that set up maybe even something like a 4.56

Jan 25, 2007 | 02:27 AM

Fordman_Evs

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From: BC, Canada

Depends on what your doing. Heavy wheelin you'd want 4.56 but if more a highway cruiser I'd go 4.10. You have overdrive which will help with the RPM, I had the exact same truck but 4 speed. 4.10 was all I wanted since she was screaming down the highway.

Jan 26, 2007 | 12:01 AM

WATTSUP!

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Thanks for the info guys! Think I'm going to go with 4.56 with a detroit in the rear and a Auburn in the front. I'll hit ya back and let you know how they perform. Thanks again!

Jan 26, 2007 | 08:19 AM

plowboy2155

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With 36" tires and your manual transmission.....here will be your engine RPM's at 65 MPH

Fourth OD

3.08 1869 1477
3.31 2009 1587
3.55 2155 1702
3.73 2264 1788
4.10 2488 1966
4.56 2768 2186
5.13 3113 2460

To find your RPM at a certain speed, here is the formula

RPM= (MPH X 336.1 X RearRatio X TransRatio) / TireSize

Jan 26, 2007 | 09:30 AM

Kemicalburns

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Joined: Jul 2002

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From: Bend,OR

i would run 4.88's with that combo. especially if you go bigger to say 38's you will still have plenty of gear.

Jan 26, 2007 | 09:36 AM

wizzard351

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From: wi

i just figured this out with 3.08's and stock tires to 36"tire and 3.93 gear would be needed to corect speedo but like every one else said id go to a 4:56 to gear it down a lil more