I jacked the rear up on the Ramcharger thinking I could get my rear axle ratio figured out by turning my whell and couting the revolutions on my driveline. I ended up with 1 wheel revolution = 1 3/4 driveshaft revolution. That doesn't seem to work for any realistic ratios I have seen. How can I figure this out without pulling the cover and counting teeth.

It is an 8 1/4"

Thanks,

bwhitejr

..sure it does. You've got a 3.55:1

You need to turn the wheel twice on an open rear with the opposite wheel held in place - or you can simply multiply *2

D/W

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If it ain't broke, fix it!

Jack up one rear wheel. Mark the tire. If you have an open rear axle, turn the tire [two] complete revolutions (Sure Grip: Just one) while watching the driveshaft and counting U-joint caps. There are four of them per revolution, so I just count the number of U-joint caps that face the ground over the course of two (open) one (suregrip) tire revolution, then divide by four, thus:

16/4 = 4 = 3.91
14/4 = 3-1/2 = 3.54 or 3.55
13/4 = 3-1/4 = 3.21 or 3.23
12/4 = 3 = 2.93 or 2.94
11/4 = 2-3/4 = 2.71 or 2.76
10/4 = 2-1/2 = 2.45
9/4 = 2-1/4 = 2.26

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

I know that is correct, because I have the build sheet for the vehicle, but why would I multiply by two?

On my son's I get:

1 wheel revolution = 1 1/2 drive shaft revolution.

The closest ratio to this that I can find is 3.07:1.

Is this correct?

No, it is not; there's no such ratio as 3.07.

Again: Rotate the wheel through two revolutions.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Because the opposite wheel isn't turning.

Due to the differential, if one wheel isn't turning, the other wheel rotates twice as much........

Note: with a sure-grip, you'll need both wheels off the ground, and both wheels will turn together.

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

THANK YOU! Very succinct way to put it. I think there ought to be a "fundamental basic FAQ" section here to answer these kinds of things.

D/W

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If it ain't broke, fix it!