Hey all,

Just in the middle of a manual conversion on my 1995 250t, I have a rear diff with an LSD to go in where an open diff used to be. If possible, I'd like to retain my current axles, and perhaps modify them if required...

 

So I've found through searching that there is a difference in the axles between LSD and open diffs, but can't find any info on exactly what the difference is, save for a vague reference to the LSD ones being 'shorter'.

 

If anyone has, or can get, photos or (even better) dimensioned sketches of them so that I could compare with my current ones it'd be appreciated.....

i found out today there are 3 different stub types, at least 3 now i have confirmed

1. the clutch type lsd (85-89) unit had stubs that have retainer torx bolts holding the stubs into the lsd

2. the vlsd of the 91 legacy had circlip stubs holding into the vlsd guts

3. The vlsd of the 2001 forester, has stubs that are molded into the axle, part of the axle, that are able to insert in.

4. I have yet to dig into my SVX to see what that VLSD is like.

OK so I've found this picture on another forum, which would seem to explain why there is another, smaller splined hole in the center of my lsd. Do these look familiar to anyone? My non lsd axles certainly don't have that extra spline, so looks like I'll need to get new axles.

Also, can anyone confirm that on a VLSD I should be able to see the spider gear shaft if I look through the side gear/axle holes?

On my diff, I can see right through to the other side, there is no shaft running across the hole, just a smaller diameter splined hole in the middle. From what I gather, this means that I have a clutch lsd... correct?

What did your lsd come from?

 

I have one out of a 2001 ouback that I can check both axles on, but the 1 I pulled out looked like the single spline axle on the right.

It came from a 1997 JDM legacy GT-B. Problem is, I don't think you got anything like that in the USA AFAIK. They share most of the driveline components with WRX STis of the same era....

 

I'm also not 100% sure that it is actually the original diff from that car, it may have been swapped at some stage for all I know....

wtf is the left axle. the one on right is the new style i talked of

never seen one on left

OK I've come across some more info that might clear this up a bit.

 

Seems the early VLSD units had the viscous clutch in the center, and required the second spline on the end of one axle. The center also looks very different to an open one.

 

Some time about 1999 they changed to a VLSD with the center clutch between the carrier and one of the side gears -- exernally, this looks very similar to an open diff. The additional spline on the end of one axle is not needed with this design.

 

So it looks like both types are a viscous lsd, they just changed it in ~'99, possibly so that the same axles could be used on lsd/non lsd diffs...?

 

So it seems the mystery may be solved. I wonder if either Viscous unit is 'better' than the other......