Gear Box Oil

[Andrew Morris]

Any suggestions on a decent Gear Box Oil, my old bottle of Hypoy 90 is now an antique and probably worth a few quid for the packaging.

Anythjng decent from Halfords? for a 1256

Thanks

[1972nail]

Whatever oil you choose go for GL4 spec as GL5 spec is too slippery for our old synchromesh gearboxes.

[jpsmit]

Whatever oil you choose go for GL4 spec as GL5 spec is too slippery for our old synchromesh gearboxes.

is this true of GT transmissions as well?

[1972nail]

Yes, I used a modern GL5 oil in my OHC gearbox when I first fitted it as that's what my supplier gave me. I found that all changes were baulky and slow, I blamed the box for being worn but before giving up on it I swapped over to Millers GL4 mineral spec and there was improvement but not a complete cure. The box was replaced and GL4 is now used in it with no problems.

[jpsmit]

Yes, I used a modern GL5 oil in my OHC gearbox when I first fitted it as that's what my supplier gave me. I found that all changes were baulky and slow, I blamed the box for being worn but before giving up on it I swapped over to Millers GL4 mineral spec and there was improvement but not a complete cure. The box was replaced and GL4 is now used in it with no problems.

and, without hijacking - do you just fill full or ???

[1972nail]

Once installed with the propshaft fitted remove the filler plug and fill until it runs out the plughole. It's easier to run a long pipe from the engine bay down into the filler plug and clamp it off like a hospital drip line. Open to fill and close to stop. Use and old bottle that you can put a hole in the top to allow air in and let the oil drain freely.

I'm sure Chris will not mind me using his photo as an illustration.

[jpsmit]

great pic! but is he filling the gearbox or the differential?

[lord13]

Looks like he's filling the diff...but it's the same principle

[droopsnoot]

Yes, I found that if you buy the oil in 1l bottles, and rely on squeezing the bottle to push it up into the filler hole, you need at least half a litre more to help it go, it seems impossible to squeeze the bottom half of the oil out of the bottle.

[StefanM]

If you want decent and easily obtainable oil you can go to any volvo dealer and get oil for manual transmission for 850/V70 or similar. They use a singlegrade 75W GL4 oil unlike many others who use multigrade GL4/GL5 oils. Part no is 31280771. Might be different in UK due to regulations, I dont know.
Same oil from Febi is 21829