Gearbox oil

[Ignatzcatz]

Our American friends say this stuff is pretty good in gearboxes. It's Swepco 201, just wondering if any of you guys have used it?

[Lightweight_911]

.

Tried it many years ago & found it no better - but significantly more expensive - than a good hypoid EP90 ...

.

[911hillclimber]

Tried 201 years ago. (915 box, fully rebuilt by MB Engineering, road and harsh hillclimb use for 14 years)
Waste, no good at all, or at least no obvious improvements, EP90 FAR better.
Once 201 is in the box it does not all come out easily, so you end up with a mix of 201 and EP90, not the ideal.
Drain the box and fill with EP90.
Leave the 201 on the shelf.

[Ignatzcatz]

Thanks for the words guys.OK so I wont be using Swepco but I did check out Quaifes' technical info and with their LSDs of which I now have in my 915 box, they recommended Fuchs synthetic 70/90 so I've ordered some from Opie down in Redruth and hopefully, in a few months when the car is all uptogether I shall be able to tell you how the stuff fares.

[911hillclimber]

Iirc 201 is meant to be super slippy etc
If the lsd is a friction plate type then 201 will affect the lsd

[Cortina]

castrol b373 is answer

[MikeB]

If it’s a Quaife ATB then the EP90 is fine, if it’s a plate diff then the B373 as Alan mentioned. Though I have heard of B373 being recommended for the ATB by THE ‘box guru

[KS]

I have a Quaife ATB fitted by Mike and he recommended EP80 or 90.

[911hillclimber]

^^^^^ same for me too in the Lola's box

[Number 52]

I have a KAZ LSD and G50 box and used KAZ oil at the last change but it is very expensive.
Anyone have experience of alternative oils for KAZ LSD?

[jwhillracer]

I’ve used ordinary EP90 in my 915 gearbox with a ZF LSD for over 30 seasons without any problems.

JW

[bjmullan]

I’ve used ordinary EP90 in my 915 gearbox with a ZF LSD for over 30 seasons without any problems.

JW

And that is what the sage from the north always recommended.

[Ignatzcatz]

Following further recommendations, my 915 with Quaife LSD is now filled with Fuchs Titan Race synthetic 75/90. I haven't an engine in the car yet so I'm afraid I'm unable to give any performance update, but I'm hoping it will be fine.

[Number 52]

Thanks guys.

[Strictly]

I can only add. Over about 3 x 915 boxed 911's where swepco was used (unknown oil before), I only noticed a difference once with swepco. It was however without doubt the best 915 box I have ever driven. Really nice! I cant draw a conclusion, as the other two boxes were getting "a little long in the tooth", with one being rebuilt a few weeks later, so maybe it works better in a "good" box in the first place.

In any case I would go with the advice above, just wanted to add the experience based upon your question.