Hello all:
I've been away from the forum for about a year & a half, doing other things including finishing my Healey restoration. I'm 80% there and hope to close the gap by year end. Just fyi, I'm not doing the full restoration/concours thing, but nor am I doing the anything-goes route. Trying the hew the middle line, i.e. mostly authentic but detouring to remedy design flaws (e.g. the cooling systen, etc.). Here's the question du jour: My differential and gearbox are OK (not super great on the gearbox, but a rebuild is a couple years out, etc...) But for a short term "tune up" vs. a rebuild, I plan to run it hot then replace the fluid. Are there any supplements out there that are worth considering? Moly stuff, etc? I know the factory shop manual says the gear action in the transmission may be enough to separate fluids, hence the question. Are supplements worth using or is it best to drain and use a high quality fuild replacement (recommendations?).
Many thanks,
-Tom

Hi Yom- ------ -------- -NO supplements--Keoke-

If you're trying to stretch a bit more life out of your gearbox I'd put synthetic fluid in (I like Redline MT-90). I don't know of any "rebuilds in a can" that actually work and, generally, synthetics are better lubricants than mineral oil. You may get more leakage from your old seals and gaskets, but might also notice a bit smoother shifting.

On the other hand, over only a couple years' driving--unless you're going to do a lot--the difference in wear between using synthetic and, say, straight 30-weight motor oil will probably be negligible.