EP90 Replacement in the 101

[stuee]

I'm looking at a replacement gear oil for the 101 steering box, steering relay, diffs and CV's.

At the moment I'm considering Penrite Gear Oil 80W-90. (I actually brought a 1L bottle of it for the steering box already)
Penrite Oil - A Better Class Of Oil


It states it is "Compatible with copper alloy components" i.e. should work okay with the phosphor bronze bushes that I have heard mentioned many a time.

From research I've done the 80W-90 formula should make it a bit nicer to operate when cold but give the same protection when warm.

Anyone using a modern gear oil in their 101 with any success? I'd like to be able to use a freely available oil rather than order one in. The vintage spec oils (i.e. Penrite Mild EP Gear Oil) all seem to be special order and most auto shops are clueless when quizzed about oils.

[101RRS]

There is nothing special about the oil that goes in those components - is all the same specs and any common mineral diff oil is suitable - the diffs in the 101 are no different in this regard to any other sals equipped landie. I usually buy what oil is on special at Supercheap or Repco - usually end up with Castrol or Valvoline. I cannot see why you would need to order anything special in.

Garry

[stuee]

Thanks Garry. I've read a few topics previously where some get quite animated over EP90 and making sure its used. Seems I've been concerning myself unnecessarily.

[101RRS]

The main issues with Ep90 are in the gearbox and tfr case but diffs etc - just brand name mineral diff oil. I am nor sure on modern synthetics in the diffs etc but for a 101 the good old stuff works just fine.

[101 Ron]

Yep any name brand EP 80w-90 in those components

If want to get fussy EP140 works better in the steering box and C/Vs, but not a problem either way.
It is the motor, gearbox and transfercase where you have to be very careful about using the correct oil.
I use a 20w/50 in the motor( have been told a straight 50 engine oil is better if you can find it.
What ever you use in the motor, use in the gearbox and transfercase.

If you want to get fussy , Castrol VMX 80 works very well with the 101s gearbox only..............it gives better smoother gearchanges while meeting the standard 101s gearbox oil specs...ie 20W/50 engine oil.

[101 Ron]

If you are playing with the oil in the diffs, do frequent oil changes on them when the vehicle is off road, as the diffs inspite of the high diff breather pipes tend to get water and mud in side of them.
I have a theory on this.
The standard diff breather fittings for the breather hose is a banjo bolt in the top of the diff housing.
The holes in that banjo fitting are very small and tend to block up.(usually with dust or rust flakes)
One of 2 things can be done.
Drill out the small hole in the banjo bolt to a bigger size or throw away the banjo bolt and use modern Festo type fittings straight into the diff housing.
Doing this little mod should reduce the likely hood of leaking hub oil seals too.