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Aug 12, 2004 | 04:36 AM

quickford

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Rpm

Want To Know The R.p.m. For 88 Ford7.3 At 65 M.p.h

Aug 12, 2004 | 05:18 AM

WhëëlMå1

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From: MA

Welcome to FTE. You left out some information. What do you have for tire sizes? How about rear end ratio? What gear are you in @ 65? Do you know that gears overall ratio?

Rich

Aug 12, 2004 | 05:35 AM

quickford

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Tire size - 16; it's an automatic 3 speed, no overdrive and I don't know rearend ratio. It's an '88 f-250 king cab with a 7.3 diesel.

Aug 12, 2004 | 06:33 AM

WhëëlMå1

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From: MA

16" tires? Are you sure that isnt your rim size? Also, if you dont know the rear end ratio, there is no way for us to determine the rpm. There should be a small metal tag affixed to the rear diff that has a code on it. With that code, we should be able to figure out what it is (it might also be listed on the sticker in the door jamb).

Rich

Aug 12, 2004 | 07:15 AM

Monsta

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From: Washington State

Quote:

Originally Posted by quickford

Want To Know The R.p.m. For 88 Ford7.3 At 65 M.p.h

Look at the tach.

Aug 15, 2004 | 01:52 AM

quickford

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Rpm

The Axle Ratio Is 4.10 A Code C-5 Automatic Transmission C6.

Aug 15, 2004 | 07:17 AM

Dave Sponaugle

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From: Nutter Fort, WV

What is known
C6 tranny is 1 to 1 final drive ratio
rear end ratio is 4.1

What is assumed
stock 235/85 - 16 tires are 31" tall

What is calculated
2900 RPM = 65.23 MPH