Hi all, which is the best gearbox oil to get these days please? Last time I changed it was about three years ago and all I remember was it was hard to get something of the right type.

GL4

75w80

http://www.halfords.com/motoring/engine-oils-fluids/gearbox-oil/halfords-gear-oil-ep-75w-80-gl-4-1l

It even has "for Citroen and Rover transmissions" written on the label.

There's two versions, one is 75/80 the other is 80/90. DONT get the 80/90, the packaging is very similar!

Awesome, thanks. The EP will be meaning the same thing as hypoid then I assume?

I had it floating around in my head that hypoid was what to look for, for some reason..

I've always been confused about oils. I just about understand the point of having a multigrade engine oil: when the engine is cold you don't want too much viscosity.

But why 75w/80 for a gearbox? It doesn't change temperature very much, and for that matter how big a difference is there between 75 and 80 anyway? Gear oil used to be straight EP 80 once upon a time (that's what is supposed to go into my H-van, for example).

Incidentally Haynes says 80w/85 for the gearbox, but what do they know?

Warning About Gear Oil
http://www.benchmarkworks.com/articles/ ... aroil.html

Do not use GL-5 oil.
http://www.citroen-sm.org/wiki/index.ph ... ission_Oil

Thanks for the link, Ken - that Smith & Allen oil looks very good value for money.

The EP80 at £13.58 for 5 litres is just what I need for my H-van, and much cheaper than the 75w/80, which is just a few pence less than £25 for the same amount. Perhaps it would do for 2Cv gearboxes too?

Hi Dennis,
I do use it in customers' A series cars and also in the 3 Dyanes we've got in daily use.
It's changed at 10,000 miles or annually, whichever comes first.
The 20 litre drums are a handy size, not sure I could drag the larger ones around...

ken