a833 input shaft seal install

90 wt is probably on the thick side; unless you're ambient temp is really high, and all the time, and you're operating under severe duty.
I don't like running EP oils in my box.It really slows the synchronization procedure. It does, however, make everything in there last forever-ish.
I like running ATF. But the cluster-pin takes a licking .Its possible to rotate the pin every couple of years, by cutting new retainer grooves at the end(s). But I found that 50/50 ATF&75/90 seems to work out OK. Eventually I modded my synchronizers to work with synthetics.Shifts like lightning!And seems to not be wearing at all.Except for the brass rings.But then;I've always been hard on them.LOL