Diff gasket? NLA?

[Black88GTA]

So the '92 I'm fixing up had a Level 10 4.44 transmission swapped in back in 2005 (which I actually do have the paperwork for), and it seems like it is working well. According to the logged mileage, this trans has less than 10k miles on it (!) However, the paperwork states something along the lines of "informed customer that rear diff swap to 4.44 gears is required" indicating that this wasn't done, at least not at the time the transmission was. I don't have any paperwork showing a rear diff swap...and I've got a bad torque binding problem I need to figure out.

Before messing with Duty Sol C or the driveshaft itself, I wanted to open up the diff and see if I can ascertain exactly what's in there, what condition it's in, and swap it with the 4.44 in the parts car if needed. But, looking around online, it seems that diff cover gaskets for this car no longer exist? I found the part # for the gasket from Subaru (383385200) but it comes up as NLA (of course), and parts stores / Rock Auto don't seem to have any either.

What's the best course of action here? Just plan on putting the cover back on with RTV only? Try to roll my own with a sheet of gasket material and a box cutter? Never been much of an arts n crafts guy, but I could give it a shot I guess. Already had to do that with taillight gaskets

[immortal_suby]

Can you raise it, spin the driveshaft, and count the axle rotations to see what the ratio is?

[Black88GTA]

Originally Posted by immortal_suby

Can you raise it, spin the driveshaft, and count the axle rotations to see what the ratio is?

I may end up doing that at least as a starting point, but I kind of wanted to check out the condition of the gears as well - make sure they're not chewed up, the limited slip unit is in place / functional, etc. I think I can put the cover on with just RTV, but would rather not do it this way if I could avoid it.

[TomsSVX]

It's always been silicone when I did them. Most modern vehicles never had a gasket

Tom

[Black88GTA]

Originally Posted by TomsSVX

It's always been silicone when I did them. Most modern vehicles never had a gasket

Tom

Thanks, good to know. Haven't had to open up too many diffs in my day, and both times I did, I had a gasket to stick em back together with so I never had to think too hard about it.

I at least know the diff in the parts car is built right...because you guys did it back in 2010ish along with the Bullet exhaust, which has found a home on the former parts, now project car