97 4.0 5 SPEED WITH 8.8 3:08 REAR

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01-18-2023

judgejohnmd

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97 4.0 5 SPEED WITH 8.8 3:08 REAR

My project truck, I discovered has the 8.8 rear; 10” brakes; 3:08 gears: trying to figure out actual MPH vs speedo reading: any suggestions?
Thanks!!
John in MD

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01-19-2023

2011Supercab

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I just use the Google Maps APP on my cell phone.

Just set a destination in the APP and leave it open and while you are driving it will tell you how fast you are going.

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01-19-2023

RonD

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Just use RPM to speed calculator, like this one: https://spicerparts.com/calculators/...rpm-calculator
3.08
27" tire diameter?
2000 RPM
trans ratio in 4th is 1

So at 2,000rpm in 4th you should be going 52mph, assuming 27" diameter tires

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