What alternative oil can i use in my 1098 gearbox

[ssnjimb]

Hello

Iam thinking about what other oil types can i put in my morris minors gearbox. Its a 69 ribbed case 1098 box.

Can SAE 40 oil be used instead or SAE 30.

Kind Regards
James Stephenson

[bmcecosse]

If you wish - most would use 20W50 - same as engine. Higher viscosity oil will cause a little more drag = poorer fuel consumption.

[ssnjimb]

at what temperature does the oil in the gearbox operate at.

20-50 is 20 when cold and 50 when hot. so if i stay between 20 and 50 i should not cause much more drag is this correct.

That is why i was thinking sae 40 as it would be a constant thickness.

My gearbox is getting a little worn anyway.

James Stephenson

[bmcecosse]

In the gearbox it scarcely gets more than slightly warm - in normal use. So probably running more at the '20' rather than the '50' - which is at too-hot-to-touch temperature, ie more than 70 C !
SAE 40 will be fine - sold in most Motorcycle places - and ideal for re-filling the dampers!