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mikep · 03-19-2003, 02:13 AM

What sort of rear end do you have? If its a C20 you have either a dana 60 or an eaton. 90% of Danas are 4.10's but there should be a tag on the rear that says the ratio and gear count. A big block auto may have 3.54's. If its an eaton you'll have to have someone turn the wheel while you count driveshaft revolutions. Remember to chock one wheel if its a open rear ( non posi ) If its an open rear multiply the driveshaft revs by 2 to get your gear ratio. If its a posi or locker than just count revs. Its more precise if you do ten wheel revs. make sure to mark the driveshaft with chalk to make it easier to keep track of revolutions.

03-19-2003, 02:13 AM	#2
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	What sort of rear end do you have? If its a C20 you have either a dana 60 or an eaton. 90% of Danas are 4.10's but there should be a tag on the rear that says the ratio and gear count. A big block auto may have 3.54's. If its an eaton you'll have to have someone turn the wheel while you count driveshaft revolutions. Remember to chock one wheel if its a open rear ( non posi ) If its an open rear multiply the driveshaft revs by 2 to get your gear ratio. If its a posi or locker than just count revs. Its more precise if you do ten wheel revs. make sure to mark the driveshaft with chalk to make it easier to keep track of revolutions. __________________ No truck :-(