Dudley

I had Guard rebuild my LSD last year and I could not be happier. I refilled my transmission with Delvac - it has been shifting Ok but it is due for a flush after a year and few track days. I ordered the Porsche fluid - is is supposed to have more friction modifiers and provide smoother shifting. I don't know if it is true but I do know it is pricey! Of course, I still buy golf ***** because the box says "guaranteed longer and straighter" .

LVDell

As the judge would say......is there a question?

GTgears

The answer is 42.

bgiere

i have run quite a few of the gear lube favorites and was was conent with Delvac and Redline 75w90 NS...until I tried Amsoil Severe Gear 75w110...best shift action so far and the cup car "rattle" has quieted a bit too. I am going to run it this season and send a few samples in for testing along the way.

P.J.S.

Amsoil severe gear here - lovely

911RufRT

Been very happy with Motul Gear 300 75w-90.

samdeshi

AMSOIL has good performance at high temperature. But i worry about the following comment on the AMSOIL web site.

"AMSOIL Severe Gear is compatible with most limited-slip differentials. If limited-slip differential chatter occurs, add AMSOIL Slip-Lock™ friction modifier additive."

Does this oil contain the friction modifier a little from the beginning?

P.J.S.

IIRC in speaking with Matt at guard - amsoil good and never add friction modifiers

GTgears

I never say never...

What I say about friction modifiers is that with respect to an LSD friction modifiers are generally an NVH item. OEMs use them to quiet the chatter of the plates by making them more slippery.

But that's not the only reason for friction modifiers. Part of why Porsche puts them in the factory GT3 oil is because the car has steel synchros and it makes them a little more slippery and easier to engage, in particular, when the gearbox is cold first thing in the morning. A lot of the track guys don't worry so much about that because they do a couple of outlaps to warm things up and once they do, the Delvac, for example, which does not have modifiers, does just fine.

However, I will add a little story from a recent customer conversation. I've got a customer in the LA area with a 944. About a year ago, he started having corner exit oversteer that he couldn't figure out. He didn't have it prior to that. He made all kinds of suspension changes and it was still there. He called me at his wits end asking if maybe his LSD needed to be rebuilt, but from what he described to me it sounded like his problem was too much lock, not too little.

And then something happened by accident. He was at an event and needed gearoil. He borrowed some from someone else in the paddock. It was a more slippery oil than what he had been using. The problem went away almost instantly and this car that was wagging its tail all the time now had a subtle push. All from a change in gear oil.

So, you see why I don't say that with gear oil one size fits all and that I never say never? I do say that for maximum locking performance of our LSD friction modifiers aren't what you want. But what if you've got too much lock? You can actually retune the LSD and change it's lockup marginally by adding a friction modifier. They are that sensitive.

P.J.S.

instead of adding modifiers, modify your oil selection