Diff Flange Dimensions

[ketvrin]

My diff may be on its way out and I was thinking of fitting an LSD from a 2WD Cossie. Now I know I need a 7.5 inch and 3.64 ratio but I have seen a warning that the output flanges must be 100 and not 108 mm (JedS IIRC)I take it this is the Outside Dia of the Drive Shaft Flange on the diff (not the prop shaft flange ?)

Can anyone confirm this for sure before I buy the wrong diff

cheers

K

ps - I know I could measure mine but I'm not at home at the minute and need to move quickly on this

[CTE]

Its too warm and I cannot be bothered to crawl under the car to measure the flange sizes, but my LSD came from a 2.9 4x4 Sierra and fitted the flanges without any problems. The other mounting holes lined up ok, but there was about a 10mm gap on one hole to the chassis which required a spacer boss.
Hopefully some help.

[Barkychoc]

My diff is off the car (and in the way like everything else I've removed!) and is a LSD ford unit but its on a V8S so is there any value measuring it? If so I can do so easily.

C

[Jed-S]

A Sierra 4x4 is usually fitted with a 7" diff with 100m flanges. To fit one of them you'd need some spacers on the diff mountings plus the front mounting is a long bolt all the way through. It does save quite a few kilos though if you can get away with a 7" diff.

The only diff I'm aware of which is 7.5" and 100mm flanges is the Granada Cosworth and if you want LSD then it needs to be an early one - BOA engined? Later Granny Cossies had traction control so dropped the LSD apparently.

[Barkychoc]

I know it doesn't help but the V8S has 108mm flange, just been out to the garage.

Could you remove your flange and fit it to another diff?

I guess it depends if the spline is the same.

C

Edited by Barkychoc on Monday 9th June 20:39

[ketvrin]

Thanks for the replies guys... it was make your mind up time so I bought an LSD Diff on ebay for £85 complete with rear support, so if its the wrong diff I should be able to sell it on OK

Its a 7.5" LSD with 3.64:1 ratio from a 2WD Cossie

I'll let you know about flange dimensions and fit later for future reference

K