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

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26 April 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...

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26 April 2010, 10:46 AM

dunx

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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

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26 April 2010, 11:43 AM

hullstu1

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

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26 April 2010, 11:48 AM

Arch

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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.