Diff and Trans oil for manual units . I was just wondering and wanting some input on the different brands of this stuff . To start with is Amsoil really better than the others ? Is synthetic beter to use? I am asking for info from actuall use not from adds. I know that the products have advanced since '73 when the manuals were printed. :classic:

I've used RedLine synthetics in both the diff and trans, not that it made a huge difference.. It did help the trans a bit making it easier to shift, but no huge improvement. Synthetics are a bit lighter in weight, which will help conduct heat out of the diff and trans, as opposed to holding the heat, while still giving you the protection that a hypoid oil will.

Unfortunately the synthetics are quite a bit more expensive. I've used them in the race car, and plan on using them in the street car as well... Call it piece of mind more than anything.

I suspect my gearbox is leaking from some form of seal and maybe the differential aswell. I recently topped up the gearbox and plan on checking the diff aswell when I get the change to work on her next.

I would like to use good oil in engine, diff, and gearbox. But am not sure if we even get Redline here in AUS.

Something I will try in future, but for the moment I don't see any point in buying good oils if it's gonna leak out or burn up in my engine.

By the way 2manyZ's is it most likely that the rear seal on my gearbox is what's causing the gearbox to leak?

If so do I just remove the drive shaft and replace the seal that way????

Thanks,

the z club of sydney just had a dyno night where we had an oil additive called Bi-tron added to a car in back to back results. made 2 kilowatts difference, it was then added to the diff and gearbox but lost the gain. weird. its supposed to cool temps and increase efficiancy and make oil stick better, comes out of canada, anyone else use it?