Finding my ratio

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78C10BigTen

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78 c10 2wd with a 10 bolt rear. How can i find out my gear ratio in my rear without peeling off the cover and counting?
 

flying2275

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If you have a open rear end, jack up one tire and spin the one tire and count how many times the drive shaft spins during 2 revolutions of the tire.

For a locking or posi jack up the rear end and spin either tire 1 revolution and count how many times the drive shaft spins.
 
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78C10BigTen

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Heres what ive got....

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Honky Kong jr

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Not to sound dumb but pull the cover I’m sure that gear oil hasn’t been changed in forever. The ring gear will be stamped and You will have to do some math but you will know and you would have serviced your diff. And don’t forget the posi fluid.
 
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78C10BigTen

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Not to sound dumb but pull the cover I’m sure that gear oil hasn’t been changed in forever. The ring gear will be stamped and I out will have to do some math but you will know and you would have serviced your diff. And don’t forget the posi fluid.
Posi fluid
 

78C10BigTen

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So is this tellng me my big ten was standard with 3.07? But option of 3.40 and 3.73?

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Honky Kong jr

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Gov bomb it the style of limited slip unit used in 10 bolts. Gov lock and they will explode hense bomb
 

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