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1986 XR4x4 Diff??
coozer - 2/1/07 at 07:49 PM

Anyone confirm the diff in the back of a 1986 XR4X4? It has a 2.8 engine.

7", 3.62 LSD, disc brakes?????

Cheers,
Steve

[Edited on 2/1/07 by coozer]


hector - 2/1/07 at 08:08 PM

Yea sounds right, thats what mine was!


Pezza - 2/1/07 at 09:15 PM

Pretty sure all 4x4's had lsd's


RichieC - 3/1/07 at 01:32 AM

Definately a 3.62 LSD. Discs as far as I can remember.

Rich


NS Dev - 3/1/07 at 08:00 AM

yep, exactly right


Syd Bridge - 3/1/07 at 09:08 AM

And I've had at least three Sierra 4x4's through my hands, and still got the remains of one mounted in a car out the back......

3.62, and 7 1/2". YES, 7 1/2"!!!!!

Not all 4x4's were 7", and to the contrary, most were 7 1/2" up to the late 80's. At least those behind the 2.8 engines.

Cheers,
Syd.


NS Dev - 3/1/07 at 09:52 AM

this is where I get muddled up!

Is that the Crownwheel bolt pcd or the casing width?

Ford call the 7" diff that because of its crownwheel pcd, just wondering if we muddle things on here by talking about casing widths??

I have had 6 ford lsd's from xr4x4's, 4x4 estates and a cosworth, and all had 7" crownwheel pcd's, but i've never measured the casing so no idea what widths they were, other than they were all the same as I've never altered my diff mount jig which I made to fit the first one, which was a 1987 vintage one!


Syd Bridge - 3/1/07 at 10:05 AM

That's cwp's, Nat.

Ford put them in that bigger case for good reason.

Cheers,
Syd.

[Edited on 3/1/07 by Syd Bridge]


NS Dev - 3/1/07 at 10:08 AM

fair point!


Liam - 3/1/07 at 06:30 PM

You sure about this, syd??

I've had many 4x4s pass through my hands, including 2.8, 2.9, 2.0 DOHC and cosworth; saloon, estate and granada. All have been 7". I've also never, ever, ever heard of any of the many locosters who've bought themselves a 4x4 back axle for its LSD ending up with a 7.5", which you'd expect to find if most older ones were 7.5".

There is also the fact that the 7.5" comes in 3.64 as opposed to the 3.62 of the 7", if i'm not mistaken. Not a huge difference but probably enough to upset the centre diff VC if a 3.64 is run with the 3.62 front diff. Certainly not a design choice the factory would make anyway.

I think if you've come accross a 4x4 with a 7.5" rear diff it's much more likely to be a later addition than a factory fit.

Liam


paulf - 3/1/07 at 07:36 PM

ive come across a 2 litre 4x4 and am considering getting the diff, will it definitely be a LSD? and I assume a 3.62 ratio.
If so how suitable is the lsd set up for a lighter car like a seven? I am thinking of using it with a dedion axle.
Paul.


Liam - 3/1/07 at 07:52 PM

2 litre 4x4 will be a 3.92. Deffo a 7" LSD though. Have a search for the many threads on the pros and cons of LSDs. Dont have experience of one in a seven myself.

Liam


NS Dev - 4/1/07 at 08:45 AM

quote:
Originally posted by Liam
You sure about this, syd??

I've had many 4x4s pass through my hands, including 2.8, 2.9, 2.0 DOHC and cosworth; saloon, estate and granada. All have been 7". I've also never, ever, ever heard of any of the many locosters who've bought themselves a 4x4 back axle for its LSD ending up with a 7.5", which you'd expect to find if most older ones were 7.5".

There is also the fact that the 7.5" comes in 3.64 as opposed to the 3.62 of the 7", if i'm not mistaken. Not a huge difference but probably enough to upset the centre diff VC if a 3.64 is run with the 3.62 front diff. Certainly not a design choice the factory would make anyway.

I think if you've come accross a 4x4 with a 7.5" rear diff it's much more likely to be a later addition than a factory fit.

Liam


thinking about it surely the flanges would need a swap as well if std 4x4 rear hubs were used as the CV joints are larger and the lobro joint bolt pcd is bigger.


Syd Bridge - 4/1/07 at 09:49 AM

quote:
Originally posted by Liam
You sure about this, syd??

Liam


Yes, quite sure. I even crawled under the one still here and checked last night. The reason I know it initially was a 7 1/2", is that I had to alter the chassis from the 7" fittings, to widen the mounts to get it in. Not just the bolt fittings, but the whole chassis assembly. Meant slightly shorter wishbones as well, to compensate.

The one here came out of a 'c' reg 4x4 ghia, with a 2.8. Also has the bigger cv's. The couple I had before it were also behind 2.8's, and 'c' and 'd' reg. And all lsd's as in the Scorpio's.

I know that when Ford went to the 2.0l dohc for the 4x4, the rear ends then went to 7" for all 4x4's. Up to then, it seems that it was 'mix and match'.

Cheers,
Syd.



[Edited on 4/1/07 by Syd Bridge]