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Sierra 7" diff or CWP set, 4.1 ratio
Inspired_dave - 22/1/18 at 06:19 PM

Does anyone have a 4.1 ratio Sierra 7" diff or CWP set they're looking to sell for cold hard pound notes or PX for a taller diff ratio (3.38, 3.6 or 3.9)?

Happy to consider complete diffs with standard or up-rated LSD (quaife, Tran-x etc).

I can travel to collect or arrange a courier collection by UPS through my work.

Please get in touch if you have or know of something suitable.

O7739 OI8 67I


bi22le - 22/1/18 at 06:39 PM

I bought a 7.5" 4.27 and angry ground 13mm off. I had to trim a fair amount off from other places aswell to get it to fit the striker.

I have not run the car since but it seemed a straightish fit.

Worth considering as the difference should be worth it.


Tommes - 23/1/18 at 06:29 AM

I have a 7" 4.27 Diff in my car. Way to short for me, lower geards are a pain in the ass and top speed of 172 km/h is not acceptabel in Germany.

I got my hands on a 3.62 7.5" with LSD from a Sierra Cosworth.

I want to switch internals, wich seems to be possible to keep the 7" housing.
This has yet to be done.
So, at the end of the modification there will be a Diff left. Let me know if shipping to UK is interestign for you or not.


Inspired_dave - 23/1/18 at 07:20 AM

Thanks for the replies guys.

Bi22le, when I first read it i thought you meant you ground the 1/2" off the crownwheel! Haha. But yes, you're right, especially as my Westfield should accept the 7.5" with no modifications except driveshafts and CV joints. However, being a weight-weenie I'm trying to keep things as light as I can for hillclimb. But if all else fails, good suggestion now I've checked, thanks!

Tommes, interesting, thanks for the info. I have sent you a U2U to discuss some more.

Still looking though if anyone else knows someone who knows someone...


bi22le - 23/1/18 at 08:50 PM

quote:
Originally posted by Tommes
I have a 7" 4.27 Diff in my car. Way to short for me, lower geards are a pain in the ass and top speed of 172 km/h is not acceptabel in Germany.

I got my hands on a 3.62 7.5" with LSD from a Sierra Cosworth.

I want to switch internals, wich seems to be possible to keep the 7" housing.
This has yet to be done.
So, at the end of the modification there will be a Diff left. Let me know if shipping to UK is interestign for you or not.


I dont think you can switch the internals. That is what the 7.5" refers to. It will be too big to fit in the 7" otherwise I would of done it.


mcerd1 - 24/1/18 at 01:00 PM

quote:
Originally posted by bi22le
quote:
Originally posted by Tommes
I have a 7" 4.27 Diff in my car. Way to short for me, lower geards are a pain in the ass and top speed of 172 km/h is not acceptabel in Germany.

I got my hands on a 3.62 7.5" with LSD from a Sierra Cosworth.

I want to switch internals, wich seems to be possible to keep the 7" housing.
This has yet to be done.
So, at the end of the modification there will be a Diff left. Let me know if shipping to UK is interestign for you or not.


I dont think you can switch the internals. That is what the 7.5" refers to. It will be too big to fit in the 7" otherwise I would of done it.


^^ what he said - but the casing isn't an issue in a dax rush - all you need to fit the 7.5" is some different bolts and spacers - the chassis suits either diff
I can give the the details of the fitment if you like ?



the only issue you'll have with the 7.5" cossie LSD in the dax is the size of the CV joints (assuming its a sierra cossie one not a granada cossie one)

2wd sierra cossies used 108mm lobro CV's - all the others used 100mm lobro's or push-in shafts.

Ford LSD's use unequal length stub axles / flanges in the diff - so you can't just swap them with the open diff type or push-in shafts
Ford only made 7.5" LSD with 100mm CV's for the granada/scorpio 24v cossie on models before traction control - so these are getting very rare now

So the only simple way to use the diffs with the larger 108mm CV's is to also swap to the cossie hubs and driveshafts at the same time