tubescreamerules

last time i checked with techican at dealer, i was told the l.s.d oil should be changed at the time around 200k km service..that's must be wrong...

340Elise

I had a really fancy ATS/Across carbon LSD and carbon clutch installed on my 340 Elise. The LSD had a break-in mileage of 200 miles which included doing figure 8's at the limit, and then 3,000 mile LSD changes thereafter, with a higher frequency with track use. The oil used (I still have some) is a 80W-90 and goes for about $90.00 for a 4 liter can.

But that is a special aftermarket LSD intended for track use, so I really don't know how a factory Porsche LSD compares.

200K km does not seem right to me either, but I have also been told that the stock GT3 LSD is not very good and might last you for 20 track days before it needs to be replaced.

That is all I know on the subject.

997gt3north

- you will not have to change the lsd oil
- it will easily outlast the clutchpack's life
- if you "track" the car, eventually the clutchpack will go and you will no longer have a "Limited Slip" Diff - you will have an "Open" Diff and new oil will not convert it back - at this point you will need a new clutch stack and off course then you will change the oil
- if you do not "track" your car, you will likely never engage the clutches in the clutch stack and at 200,000 miles or even 2 million miles the oil will still be good
- what would be interesting to know is has any gt3 ever produced hit the 200,000 mile mark?

MarekN

GT3North, call me in 16 years, I should be there by then.

tubescreamerules

[QUOTE=997gt3north;5647350]- you will not have to change the lsd oil

- if you "track" the car, eventually the clutchpack will go and you will no longer have a "Limited Slip" Diff - you will have an "Open" Diff and new oil will not convert it back - at this point you will need a new clutch stack and off course then you will change the oil
QUOTE]

if i change the oil more often, say,after each track event, would the clutchpack last longer??

tubescreamerules

340Elise, so the carbon one will stand for 3000 track miles??

mooty

i am not mechanically adept. but i thought in our cars the LSD and and the gearbox share the oil? if so (now that's a guess) i would change it quite often.

911/Q45

Not a GT3, but lot's of track use. I change mine every 50K miles. It was opened and checked at 100K (as long as the engine is out, let's check everything) and all was perfect and unworn including the lsd clutches.

RWK

I have a guard LSD and replace the clutch pack every year. MAybe 20 track days.

OldGuy

Don You NEED a GT3! its time yodasan.

Bob Rouleau

Motorsport says to change the transmission oil every 10 hours of use on a GT3 Cup! Dunno abouty differential oil. Is it the same fill or separate? When I change my tranny oil it comes out pretty black so I change it every 10 hours of track use.

best,

340Elise

Ah, good point! That was the case in my Elise and I would expect it to be true for most mid-engine or rear-engine cars?

340Elise

"and then 3,000 mile LSD changes thereafter, with a higher frequency with track use."

They may have said every 1,000 miles or less depending on how much track use. If the LSD and tranny do infact share the same oil, then it seems like a good idea. As one poster noted, he changes it with 10 hours of track use on a Cup car (did I get that right?) and it is black.

But don't forget what I mentioned about the life of the LSD, which I had learned from 997gt3north, is that it won't last that long anyway if you track the car frequently, or the oil should last as long as the life of the clutch packs. So according to him, the whole thing may be a moot point.

mooty

i spoke to tech.
the LSD and gear box is one box, called transaxel in our cars.
the oil is in the same big pool. they SHARE the oil.

i change them every 1500 trk miles, approx. 10 track days. like bob, my gear oil looks black and dirty.

mooty

are you talking about the clutch pack in OEM LSD or the guard clutch pack that you need to change every 20 trk days?