Gear Box oils

[cjcarlos1977]

Hello there,

Does the gear boxes in a 1976 take Ep90 gear oil or engine oil? This may seem a stupid question to ask im gonna be under her tomorrow checking and as this is me first landy im not sure.


Cheers

Carl

( Series 3 1976 )

[Xtremeteam]

ep90 in the series boxs i think

[blackbob]

:D yes it is ep90  :D

[hobbit]

All the underside takes 90, diffs, gearbox, transfer box, swivel housings.

[Rich_P]

Remember to put in EP90 GL4 spec and not EP90 GL5, into the gearbox or you may find you loose syncro on all gears with some damage to the gears themselves.

[cjcarlos1977]

Cheers thanks for your help!

Carl

[ian_s]

Remember to put in EP90 GL4 spec and not EP90 GL5, into the gearbox or you may find you loose syncro on all gears with some damage to the gears themselves.

really? i'b better check what oil i've bought.

[Rich_P]

Yeah, I was surprised.  But looking in the manual for the Series 2A gearbox, it needs GL4 spec.

[cjcarlos1977]

Drained and topped up all the right places today. Mines a Series 3 1976. GL 4 is a lil hard to get hold off as everywhere seems to have GL5. But i found 10 litres of the stuff so grabbed them and off i went. Got some spare now which is handy.

Carl

( 1976 Series 3 )

[Rich_P]

I'm still looking for a supplier for a fair amount of EP90 GL4.  I need some, but can only find GL5 spec.  :(

[cjcarlos1977]

Yes I had that problem aswell. Seems GL4 is a little rare these days. I walked into my local car spares shop and grabbed the last 5 litres of it, put it under my arm paid the fella behind the counter and ran like a girl home! Only to open up me shed to find...........yup a half full 5 litres tub in there!


Carl

[Miniman]

GL5 is a different spec, and is not 'backwards compatible' with GL4.

GL5 gear oil is a lubricant with very high extreme pressure performance needed for Hypoid gears where sliding and rolling contacts operate under very high loadings.  This is achieved by incorporating high concentration of sulfurized additives.  The downside to such high sulfur in oil is it tends to corrode yellow metals, so can ruin parts like brass synchronizers and some bushings.  So any equipment needing GL5 performance is designed taking this limitation of the lubricant into account.

GL4 oils are much more friendly to yellow metals, and so are used in equipment where such high load sliding-rolling contacts aren't present.  The designers of such equipment aren't as limited in the use of brass parts.  So the bottom line is that if your equipment calls for GL4 it probably doesn't need GL5 performance, and you may be asking for trouble down the line if you use a lube it wasn't designed for.

This is just so you know WHY.... Its good to know why.