Classic cars forum & vehicle restoration.

[Stuart2u]

.......Following on from a related topic....My 1948 8 E is dropping so much oil from the rear gearbox casing drain hole that I need now to top it up. My manual says to use 140 grade, giving a list of manufacturers named products (of the time).

Really......do I need such a heavy oil? I dont think that this is whats in the box at the moment....probibly 80/90 tops. It might be why I am loosing oil, but how difficult would it be to get gears in cold weather!!!!!

I have looked for 140 oil on t'interweb. I can get Castrol Classic 140 D which is a non EP (Extreme Pressure) product and a Millers Clssic Green 140 GL1 which is also a non EP oil. There are also similar graded EP oils available. Also a multigrade 85/140 gear oil which sounds like a better option.

However, the morris manual list of oils suggest an EP type.....

So any thoughts as to which one to use.......

Stuart

[Kelsham]

My 1932 BSA Trike uses Castrol D oil in the gear box. It changes gear OK.

I would use the same in the Morris if it were mine. Bear in mind that the viscosity ratings are different between engine oils and gearbox oils and do not relate to each other.

140 in a gearbox is not as thick as you would expect when warm.

Kels.

[colwyn500]

Based entirely on Austin experience, I would use the correct SAE 140 non-EP.

The additives in EP can corrode bronze bushes etc. and Kelsham is correct in that it is not as thick as you would think; although you'll struggle to get it in a small filler hole in cold weather.

Personally, in a car of this era I would tend towards slightly under rather than over-filling with oils. Obviously that makes it even more important to check it regularly, which we should do anyway. The more you can reduce the bulk of the oil swishing into the sealing zones the better. Although also bear in mind that seals, especially the old leather ones do need a certain amount of oil on them in order to work properly.

[Stuart2u]

Thank you guys.

Got a couple of llitres of Millers Classic Green 140 without the additives. Not as thick as I expected, but plainly more substantial than the oil I drained off.....and it did take a while to flow through the narrow end of the funnel when I poured it in.......it might just help stem the leak prior to getting the gearbox out during the winter.

Regards

Stuart

[mikeC]