JasonAndreas

In the 964 manuals Porsche specifies Silubrin S and I just checked the 993 manual and in the LSD sections it calls for LiquiMoly PU53 but in the regular differential section Optimol HT2 + 2EP. I have regular Optimol HT and Olista Longtime 3EP but not HT2+2EP. For liquimoly Google translation comes back with, "the forces of evil LM PU 53/WDR Grease (LM PU 53/WDR Grease)". Hopefully their New England distributor will have something.

ZombiePorsche44

Driving on LSD is Bad!....very very bad!.....but very very good for getting off a corner like a bat out of hell, even on the streets!

ZP44

TCallas

I think your worrying a bit too much. A good coating of grease or Vaseline will be just fine. It worked on the GT1, GT2 & GT3R/RS/RSR race cars for Le Mans and it still works for the Gearbox meister Brian Copans.

PaulWood

LSD, LSD!! and not one crack about Haight-Asbury. Were any of you guys even around in the '60's? [OT, but couldn't resist.]

JasonAndreas

I don't know if I would describe it as worried but ya. It is kinda interesting that both of the Porsche recommended lubricants cannot be imported into the USA without a lot of paperwork (if at all) because of their heavy metal content.

I can't get the LiquiMoly in this country either so I ended up using Olista Longtime 3EP. The manuals kinda/sorta call for it and I had to pack the input shaft seal with it so if it works for that.

JasonAndreas

Just an update...

A supplier for LiquiMoly PU35 is your friendly neighborhood Porsche dealership, Part No #000-043-110-01. And of course I had a white tube of this stuff sitting on a shelf in my house all this time but no clue that it was that.

avorkinn

Can anybody tell me why LS oil isn't described/recuired in the manuales as long as this is a disc LSD?

viperbob

By the time you find a used LSD, get a rebuild kit (factory kit is about $900. Motorsports is less but, many of the shops will not be able or know how to buy from Porsche Motorsports) and pay the labor to rebuild it you might as well have just bought a new unit. I personally like the Guards pieces better, but the Motorsports ones work just fine.

Like Tony had mentioned, finding a proper shop is key. The factory manual tells you how to do the measurements with the tranny out of the car and the diff cover pointed up. Installing it in the car with the diff cover pointing sideways and the LSD unit wanting to fall out of the car is a little challenging, but very doable for a good shop. Also before you commit to the work with a shop, find out how they install it. The best most precise way is to measure the old diff at certain points, measure the new one calculate the differences and the shims that were already on the old one and you have a pretty good starting point. Many shops do not have this type of equipment so they simply start by putting the same number of shims on the new one as the old one. This is a trial and error method to get the proper pinion backlash and bearing preload. This trial and error can take 8-14 hours (I have seen many diffs installed with these times), cost a lot of shims to be eaten up that you pay for. If the shop has a method of precisely measuring the diffs, then as Tony said it is a 3-5 hour job roughly.

luv2ride

Still On-Topic,

My 993 is a plain jane with no LSD. My last track day I was driving allot faster and more aggressive in my 4th session. I had to pass a 997 c4s and I did. Before my run I went out with my instructor in his car and quickly realized that I could be driving much faster. So near the end of the session I tracked into a turn to soon and started to run out of track and turned the wheel a bit to much and started to spin. Yes the a$$ came all the way around 360 in the middle of the track. So my question is if I had LSD would I have been able to prevent the spin? What is the difference in driving characteristics of LSD vs Non LSD?

Ryan

Mark in Baltimore

IMO, LSD would not have helped you at all. You recognize that you turned in too early and began to run out of track at track-out. Your choices were to hit the wall, go off track or turn in more. It sounds like nothing bad happened.

A clutch-type LSD is great for stability under heavy braking and can be beneficial in slower, tighter corners where you might want to trail-brake to turn the car. Before my car had LSD added, the worst turn that I experienced RR spin was the right-hander off of the back straight at VIR's south course. All of that power was going into the air.

Paul902

Interesting thread... I have a factory LSD with worn out plates I will be replacing this winter. Is it a fair assumption that if the bearings are not to be replaced that I can reuse the old shims and the backlash settings should just be right?

Interesting discussion on grease, too. It was difficult to find, but I was able to purchase some LM47 wheel bearing grease with molybdenum disulfide at a specialty shop.

luv2ride

Yea it wasn't all that bad, seemed like slow motion. But it could of been worse in traffic and if I slid off track into a wall. Needless to say the next day I took it a bit easier and didn't try to pass my friend in the 997. Need to work on ego and discipline. And it to was a right hander before "no name" at LRP and to boot the sun was low and in my eyes.

Thanks

Mark in Baltimore

I guess this is also a case where judicious use of left foot braking and proper steering input might have kept you on track, but I have no idea how much speed you were carrying out of the turn.

Paul902

993MI,

I forgot to mention... another option is get a cast unit from Paul Guard. I was speaking to him about a month or two ago and he plans to make a cast unit available for those that do not need the strength of the chromoly unit and want to save a few $$.

cheers,
Paul

viperbob

Not sure what you mean here Paul if you are rebuilding, or getting a new case. If you replace the case, you need to reset all the clearances (and you should replace the bearings when you install a new case anyway...). The variance case to case is too large.