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Sierra LSD
chrilla - 16/8/13 at 09:36 PM

I have a sierra 7" LSD diff with no tag on, disappeared when I sandblasted it, so I turned the pinion and counted the revs.
I expected it to be a 3.92 and hoped it to 3.62, but I get it to be 4.25ish. Didn't think there was a 4.2 in a 7" case.
Can any one confirm that there was a 4.2something or have they changed it sometime. The donor was a -92 4x4 dohc 2.0i 120hp.

/Christian

CNHSS1 - 16/8/13 at 10:13 PM

2ltr 4x4 was 3.92 from the factory, no cars left the factory with lower than 3.92 in a 7" in the uk to my knowledge, although theres a 4.27 in the 7.5".

There are aftermarkey 7" CWPs 4.1, 4.4, and 4.7 iirc, raceline and sbd being common. Whip the backplate off as ratio is stamped on crwnwheel by ford, no question what the ratio is then ;-)

If its an aftermarket cwp, be interested in purchasibg from you if it doesnt suit your needs? Have a few differing cwps for swapsies too

chrilla - 17/8/13 at 05:50 AM

quote:
Originally posted by CNHSS1
2ltr 4x4 was 3.92 from the factory, no cars left the factory with lower than 3.92 in a 7" in the uk to my knowledge, although theres a 4.27 in the 7.5".

There are aftermarkey 7" CWPs 4.1, 4.4, and 4.7 iirc, raceline and sbd being common. Whip the backplate off as ratio is stamped on crwnwheel by ford, no question what the ratio is then ;-)

If its an aftermarket cwp, be interested in purchasibg from you if it doesnt suit your needs? Have a few differing cwps for swapsies too



I'll pull the backplate off and see what it says on the crown wheel.
I have a zx12R, so a 3.38 would be the thing for me, unfortunately I live in Sweden so the shipping would probably cost more than buy a new one. If it wasn't for that I would gladly swap with you.
I found a 3.38 with push in shaft on a scrap yard, is it possible to swap the crown and pinion to my lobro diff or better, my lobro diff to the other case, the 3.38 have only 45000 miles on it. Guess the bearings are better then mine and maybe I only have to shim the crown wheel in place.

CNHSS1 - 17/8/13 at 09:36 PM

I have a 3.38 crownwheel and pinion set for swaps if it helps, but essentially all 7" cwps are interchangeable although usually has to be as pinion and crownwheel pair