LSD Diff Capacity

[stuartgb100]

Just filled my Salisbury plate diif with oil.
I put 1 US quart in it (0.946 litres) of Redline 75W90 and left it to settle overnight.

The Workshop manual says 1.2 litres is needed for a standard diff.

When I undid the drain plug this morning, oil poured out.
I expected none would come out and that I would have to top it up until it did dribble out.

What to do ?

Do I tighten it up and leave it as it is ?
Do I let it drain out until it reaches a level where no more oil is coming out ?
Do I tighten it up and then add approx. another 200ml to give the stated 1.2 litres ?

Confused !

Regards,
Stuart.

[Craven]

Hi,
If you are filling the diff unit in the normal way, the filler plug is in a position where it acts as a level indicator. Therefore it is self-limiting in quantity of oil carried, the level is set such the internal oil seals are not overwhelmed.
FWIW
Ron.

[billwill]

What did you do to ensure that all the original oil was out of the Diff ?

[CBUEB1771]

A limited slip differential will displace more volume inside the diff nose and housing that will a standard diff, hence allowing a bit less lubricant to get to the fill level.

[rgh0]

What did you do to ensure that all the original oil was out of the Diff ?

The later diff housings have a drain plug the early diffs did not and you need stick a tube in and suck out the oil if you want to replace it !

cheers
Rohan

[stuartgb100]

Thanks all for the replies.

Rohan, am I right in thinking you have an lsd in your race Elan ?

What level do you fill to, or what quantity do you put in ?

Too much oil and pressures will increase, too little and I sense something letting go ....!

Thanks.

[rgh0]

HI Stuart

Yes I have a Quaiffe LSD in my Elan.

I just fill until oil starts coming out the fill hole and then put the plug in quickly. It takes less than the book says as the Quaiffe diff centre is much bulkier than the standard diff centre but I have never measured specifically how much less.

The important thing is to have the oil at the correct level for good splash lubrication of the internals of the diff. This level is set by the fill plug so whatever quantity gets you to the fill plug is the right amount.

cheers
Rohan

[CBUEB1771]

Too much oil and pressures will increase, too little and I sense something letting go ....!

There is a breather at the top of the diff housing. Unless something goes wrong with the breather the pressure inside the diff will stay constant.

[stuartgb100]

Rohan, Russ,

Thanks.

Yes, I've checked to make sure the breather is clear.

Rohan, I've sent you a pm.

Regards,
Stuart.