I'm sure this has been discussed before, but what oil should I put in my 3.62 XR4x4 LSD diff ?

Asked at Ford the other day all they could say was "I know it's a special one" !!!

Was intending to buy they stuff that Ford supply, however in the light of the above that is now looking some what difficult.

If anyone has the Ford Part number, I would be very grateful for it.

I got mine from Burtons. It's a general LSD oil, I'll try and dig out the name/spec.

thanks, Ford helpful as usual.

think the part no. should be 1121457, i enquired about it a few months ago at my local dealer - needless to say they didnt stock it and i still need too.


cheers
colin

Just need EP 90 oil no special LSD oil required as it doesnt have clutch plates the LSD is a sealed unit Viscous coupling

Standard EP90 ? So that's the special stuff Ford talk about ?

I managed to chase the Ford part number down today was same as colibriman states : 1121457 £7.48 per litre. But they will need to order it in from main stores.

do NOT use special LSD oil in the rear viscous diff from a sierra.

use a known brand good quality EP90 gear oil.

have seen one to many diffs die thru use of the wrong oil.

thanks graceland so what's a "good brand" and how much of the stuff do I need (the diff is empty).

Are we talking Halfrauds or Motor factor ?

The filler is also a level plug.
Just pump or pour until it comes out of the same hole at the rear of the diff............

So what's the general opinion - special LSD oil or normal Hypoid 90 diff oil?

The Ford main dealer gave me a part number but said it would have to be a factory order.

I have picked mine up today and can confirm that the part # is 1121457 and the magnetic filler plug is 6118746 although the latter I had to buy two which was the minimum order. I ordered all of it Friday and picked it up the next day. The bottle does have limited Slip Diff oil written on it on a Ford Label.

£7.50 for the oil and 4.52 each for the filler plugs.

I agree with the other posts,normal EP 90.
I did check as well in a couple of trade oil lists just to make sure.
EP 90 is usually tacky to touch and stinks to high heaven,a bit like household gas(dont ask how I know that).

PS i think I should perhaps explain that one:I once had the Gas board round at 9 o'clock one night as a gas leak had been reported by a passer by.
I had been burning EP 90 in the waste oil burner in the garage on a cold night a few years ago.It does smell like a gas leak!

Just to check, those buying the stuff on special order from Ford..............you were buying oil for the diff casing and not for the Viscous unit weren't you?????????

The viscous unit obviously uses a special fluid, but you won't have drained that out!

The diff casing (i.e. carrier bearings and CWP) just use EP90 as said several times.

The old Atlas and English plate type LSD's do need special LSD fluid, or EP 90 plus additive available from ford, but you do don't use these in a "normal" diff! (i.e. a sierra Viscous one, which oil wise is perfectly normal.!)