Gearbox oil

[KenFern]

Hi,

I have just drained the oil in my gearbox and what came out is thick and black and smells like EP90, my manual says the oil should be 20/50, is this still valid or has it changed to the EP over the years.Any advice appreciated.
Thanks

Ken

[RobThomas]

20/50 engine oil is right. Axle/diff oil is EP90 so I guess someone just put in whatever was handy.
Rob

[KenFern]

Thanks Rob

[mike.perry]

Give the gearbox a good flush out, there are chemicals in EP oil which destroy some of the components in A Series boxes

[bmcecosse]

It may have been filled with EP90 to quieten it down.......... Engine oil is the correct fluid.