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Ok, did the usuall search thing. Came up with one topic that was pretty much useless in the general mantaince section. I think the topic would be better in this section as its a more performace/handlening related item.

Anyway, which diff oil do I use!? Even the mechanic doesnt really know as he has never come across a 2way before (more so he knows Im picky and wants to make sure what I want goes in)

Basically what Im worried about is the few people I have asked have susgested normal LSD oil, and I get this funny feeling that using that type of oil would not be too good for the diff.

Also, the diff tention settings (if the diff has them) how would you know how, and what you need to change, like is it an obvious thing, or do you need a 20 page instruction manual to work it out.

As always any help is greatly appreciated.

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Anyway, which diff oil do I use!?  Even the mechanic doesnt really know as he has never come across a 2way before (more so he knows Im picky and wants to make sure what I want goes in)

Just use a good quality mechanical LSD oil, hypoid GL5. If your planning on track work or other hard use, consider a synthetic. Personally I use Penrite oils.

Also, the diff tention settings (if the diff has them) how would you know how, and what you need to change, like is it an obvious thing, or do you need a 20 page instruction manual to work it out.

For clutch pack LSD's and similar it's normal to measure the break-away torque. Basically one output shaft is held stationary and the torque required to get the other o/p shaft to move is measured using a torque wrench (and some form of adaptor). The measured torque is a measure of the amount of 'lock' in the centre before the wheels start to go their separate ways, as it were. Stock Nissan centres have a fairly low break away torque, in the region of 30ftlbs or so, but extra plates can be added to make the diff pretty much fully locked. This would be a pain for street driving tho. We aim for a break away torque in the rgion of 70-90ftlbs as a compromise for street and some track work.

Putting in extra plates requires dis-assembling the centre and should only be done by someone that knows what they're doing...

There are other types of LSD (eg Torsen), but I'd say the majority are variations on the clutch type, particularly with Nissan's

I used a Valvoline LSD oil when i changed mine,i think it was 85/120?? it was a while ago i changed it so couldnt be 100% on the grade.....

Would be very interested to see peoples opinions on this because since the change everythings working fine, but a little "clunkyer" when tuning at slow speeds....ie: U turns.... people often say to me 'whats wrong with your diff?", kinda hard to explane that its normal

:(

I used a Valvoline LSD oil when i changed mine,i think it was 85/120?? it was a while ago i changed it so couldnt be 100% on the grade.....

Would be very interested to see peoples opinions on this because since the change everythings working fine, but a little "clunkyer" when tuning at slow speeds....ie: U turns.... people often say to me 'whats wrong with your diff?", kinda hard to explane that its normal:

Sounds like chatter. There's an additive you can get that helps overcome this problem, but of course there's no guarantee. I know that Penrite make one:

http://www.penrite.com.au/nextpage.php?nav...view.php&id=114

They also have a very helpful technical dept (...no I don't work for them :()

Well mine got changed with the stuff the mechanic had, seems a lot smoother already (mind you the stuff in there was black, and there seemed to be a rock *dunno but, could have been on the outside*)

It was valvoline stuff 90-something. But yeah, as I said, less cluncks, and a fair bit smoother.

This is what we use;

Engine oil = Castrol Formula R Synthetic 10W60 or 0W40.

Brake Fluid = Castrol SRF

4WD Transfer = Castrol Transmax Z

Auto Gearbox= Castrol Transmax Z

Radiator = Castrol Anit-Freeze Anti-Boil

Diffs = Castrol SAF-XA 75W140

:)

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