how can i tell the difference between a 3.9 and a 4.1 rear diff ?

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Apr 26, 2010 | 10:26 AM

hullstu1

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how can i tell the difference between a 3.9 and a 4.1 rear diff ?

been working on impreaxas for a while now and broke a few so i have the bits on shelf, but i seem to have mixed up a gearbox and diff and now dont which one goes with which ? doh. i have 5 diffs to choose from and only one box, any help would be great thanks...

Apr 26, 2010 | 10:46 AM

dunx

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From: Slowly rebuilding the kit of bits into a car...

For 39 turns at the input flange the driveshaft will turn 10 times..... 3.9:1
Or open up and count the teeth.

HTH

dunx

Apr 26, 2010 | 11:43 AM

hullstu1

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yeah thanks a lot never really thought about that lol thanks.

Apr 26, 2010 | 11:48 AM

Arch

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From: Scotland

Take the cover off the diff and the rstio is stamped on the crown wheel. As for the box use the gearbox code and charts to find out what its drop gears are and FD ratio.