Hewland Mk9 Gear oil ?????????????

[captiv8ted]

Hi all,

I need to do some work on the FVL's gearbox and am a little stuck regarding replacement oil. EP90, no problem there, but when I went to get some earlier, there is a choice between GL4 and GL5 spec. Something to do with additives I believe. I am told if wrongly selected, damage to seals can occur.

Anyone care to hazard a guess which one is right?

Nick.

[Nick Harrison]

GL4 and GL5 have similar anti scuffing additives.

The higher the number the better the grade.

For our short 15 min races I would use a lighter, 75w fully synthetic. You can get it quite cheaply on eBay in 25 litre drums.

If you change that on a regular basis, say every two/three races you will be surprised how long a transaxle will last without a rebuild.