Slow f350

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Feb 27, 2006 | 07:42 PM

flram

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Slow f350

I just got a 89 F350 7.3 with a 3 speed the truck run 65mph at 3500rpm can anyone tell me what gearing it has and what gearing I need to lower the rpm's for highway driving

Feb 27, 2006 | 08:09 PM

dieself250

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From: NC

what size tires do you have? what axle code do you have on the sticker on the door post

Feb 27, 2006 | 08:20 PM

flram

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265/75/16 trans code is c5

Feb 27, 2006 | 08:21 PM

flram

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axle code is c5 trans code is k

Feb 27, 2006 | 08:37 PM

dieself250

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From: NC

c5 is 4.10 limited slip

Feb 27, 2006 | 08:51 PM

Dave Sponaugle

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From: Nutter Fort, WV

Working the numbers 30" tires, a C6 automatic, 3500 RPM, 65 MPH = 4.56 gears

Do you pull or haul much weight?
The C6 automatic is a direct drive high gear.

I have a 4 speed direct drive high gear and 3.55 gears and have 285/75-16 tires that are 33" tall. 3500 RPM puts me at 96 MPH.
2600 is 70 MPH.