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roger0080 · 12-01-2005, 12:53 AM

I am just guessing in that you are doing it wrong. With an open the diff the rev count is off by a factor of 2. When you spin an open diff and count all the revs, you either have to divide it by 2 or multiply it by 2 I cannot ever remember which.

So just playing here, if you figure 2.08 is the ratio; then 2.08 x 2 = 4.16 or really, a 4.10 rear end. Which is very popular for that axle. That's my guess.

12-01-2005, 12:53 AM	#46
roger0080 Registered User Join Date: Nov 2000 Location: Carver County, Minnesota, USA Posts: 627	Re: Please verify Differentals 72-3/4 4x4 I am just guessing in that you are doing it wrong. With an open the diff the rev count is off by a factor of 2. When you spin an open diff and count all the revs, you either have to divide it by 2 or multiply it by 2 I cannot ever remember which. So just playing here, if you figure 2.08 is the ratio; then 2.08 x 2 = 4.16 or really, a 4.10 rear end. Which is very popular for that axle. That's my guess. __________________ 72 Chev C-10 90% restored (former AZ truck) ... 71 Chev K-20 Cheyenne my vacation crusier... 72 Chev C-10 Now retired and striped after many faithful miles... 72 GMC 1500 Retired to the junk yard after bought new in '71...