Diff experts please help

[Gannon]

About 6 months ago I acquired a VLSD centre from a 04 XT Forester with plans to put it in my Outback. I have since collected a 98 Outback diff to use as a donor.



So I pulled it apart and put the LSD centre in it and checked the backlash.





As you can see, the wear is on the inside edge of the crownwheel in both forward and reverse.

If I swapped crownwheels so that the original from this diff was now on the LSD centre, would it improve things? Otherwise I am gonna have to myself a shim kit. Ive read some threads on other Subaru forums to just whack it in and dont worry about the backlash, but this is a daily driver so I want it done propperly

I also need to get a smaller torque wrench because the lowest setting on the one I have is 40NM

[ScubyRoo]

A shim kit is definitely worth it if you can't get the right backlash. Are both crownwheels the same tooth count? The side shims move the bearing retainers in and out so as to change side pressure on the diff, but you might also need to adjust the 'stick out' of the pinion shaft, something I never managed to figure out.

If your diff skills are A1, good luck! If not, as it's for a daily I would suggest you consider taking it to a gearbox joint and get them to do it - worth it as they paint it up and get it 100%. It'll cost you more cash but the peace of mind might be worth it...

Cheers,
Owen.

[Gannon]

I just swapped crownwheels and the backlash seems to be better, but to reassemble the diff propperly, I need to torque the side retainers to the correct torque, but I dont have a torque wrench that goes as low as 7.6ft/lb. I want to re-check the backlash once these are torqued propperly
I also dont have locktite for the crownwheel bolts, even though I torqued them to 76ft/lb

[El_Freddo]

Generally the go is you take the LSD centre and swap that for the open centre on the donor diff. So you need to swap the donor ring gear onto the LSD centre.

Don't touch the shims, just remember which side each side plate came from and she'll be apples.

That's what I've read anyway - Andrew T is the one that's done this the most from memory!

7.6 foot pounds, you should be able to do this easily but the guesstimate hand pressure

Cheers

Bennie