Gearbox, Trasnfer BOx & Rear LSD Oil For LJ70 2.4 1992 Manual

[Yorkshire Devil]

Hi there. Can anyone reccomend a decent oil to use in the transfer box, manual gear box, front axle & a suitable oil for the LSD.

Can you use a fully synthetic in the gear box, does it make a difference from a cold start?

[mj1226]

Hi there. Can anyone reccomend a decent oil to use in the transfer box, manual gear box, front axle & a suitable oil for the LSD.

Can you use a fully synthetic in the gear box, does it make a difference from a cold start?

I have the same query as Yorkshire Dev. Anyone got an angle on this?

I'm mainly using mineral oil based, Tranny/Gearbox/Transmission oil for now. (castrol bp, exxon mobil, caltex, shell ATF doesn't matter since it is mineral and from major manufacturers)
I am hitching on a hunch that a synthetic might be better but I'm not sure.

Can anyone follow through?

[TonyN]

I use Comma oils in all the trucks I service.

Gearbox / Tcase get ... EP80W-90 GL-4
Diffs get.................... EP80W-90 GL-5
LSD diffs get.............. LS80W-90 GL-5

You can put GL5 in both to save time, although GL5 is really for high shock load hypoid gears, and not really designed for transmissions and there a slightly different friction specs but in the real world it makes little difference. Unless you want trawl through the internet, and then you'll find wild arguments from 'experts' like usual.

(Did you know that most engine oils meet GL4 spec)

Unlike engine oils there is no real issues in synthetic gear oil in older cars, but the extra expense, and maybe leakage though worn seals that you'd not notice with the semi-syn/mineral oils, but I'm not sure you'd see to much beneft, maybe slightly less drag on gearbox and diff, but whether you'd notice it I don't know.