Which Diff Questions? - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

Jakobi · 11-17-2004, 20:46

Hey everyone,

I am in the process of upgrading from my 3.08:1 single spinner to..

a) 3.23 LSD (Fairmont Ghia/Fairlane) ..or..
b) 3.45 LSD (XR6)

What I would like to know is, is it possible/easy/cheap to open up the existing diff and convert it to LSD and change the diff gears.. or buy a complete diff and axle assembly?

Also, some rough figures on how much either of these options will cost?

I am aware that the 3.45 will give me better pull off the line than the 3.23 and a bit less economy on the highway (but would still be my personal preference).. but are there any problems that can occur using a diff from a later model? i.e. changing speedo gears to get accurate readings etc..

Walkinshaw · 11-18-2004, 00:05

hard to find 3.23:1 LSD, came in optioned Fairmonts/V8's

3.45:1 will be in XR's or EF2==> Ghias

3.45:1 Disc to Disc shouldnt cost more than $700 from wreckers.

Having your center converted to LSD will cost more. Your current diff is a 25spline 2pin unit. You would need a 25spline (re: older) LSD hemisphere to retain your axles, which go for arround $550 new.

Id be looking at a whole XR6 Diff. Your trailing arms will need new EB style bushes pushed into them and if you use EF==> diff your handbreak will need altering. Also, being EA your tailshaft will need to be changed to the Flange Type EB==> style to run a 3.45:1 LSD diff.

If i was you. Id look at getting a 3.91:1 LSD center slotted into your diff with new 28spline axles.

TIKFD6 · 11-18-2004, 03:30

If your going to make the effort to change the diff, go for a 3.45
As Walkiy said try to get an EBII or ED XR rear end, and just swap it over.
It will make the whole thing that much easier.

Jakobi · 11-18-2004, 20:24

Damn EA's.. Nothing is ever plain and simple..

Sounds like alot of effort to get a complete rear end assembly.. and a 3.9 (which would make my car so much more fun to drive) isnt really practicle as I'd be chewing more fuel than I can afford.. hehe..

Might just keep my eyes peeled for a 3.23 LSD from an EAII Fairmont or Fairlane.. I guess if its meant to be then I will find one.. If not I'll just keep saving the dollars..

Thanks for your help!