Paul902

Hi,

In the process of trying to determine if my LSD is still working I noticed that I do not have a G50 20-2, but rather a G64 20-2. I know that the "-2" indicates LSD. What I am curious about is the G64 rather than G50. Do I have the proper tranny? What are the differences between G64 and G50?

thanks

RallyJon

The G64 is the AWD version of the G50

Garth S

Hey Paul,
Your query prompted a post on my limited trans surgery - so you can see the business end of what makes a G50 become a G64 - which is what you have.

With the trans in neutral and all wheels in the air, turn one rear and the other three should turn somewhat. That verifies that the viscous coupler is not slipping excessively, which is one failure mode: the other is that they can lock up - and that would be like driving a conventional 4WD on dry pavement ( the steering would bind/chatter when turning).
To test the LSD ... I suspect that if one rear is held, it would be difficult to rapidly turn the opposing wheel; however, it should turn slowly without locking the clutches - for it must still function as a differential.

Paul902

Thanks Jon.

Thanks Garth. Interesting pics. Man, you are "in there".

Regarding testing the VC, I'll have to check tonight. The car is currently on jack stands. This morning I tested to see what happens at the rear wheels but forgot to check out the fronts. Regarding the LSD, I've been doing lots of archive reading. Not certain if mine is functional but it seems like one can't tell without a specific test involving removal of the rear axles. Hmmm. I was just interested in finding out if it still worked before I bothered to change the oil. BTW last Friday I wrote to several lubricant distributors across Canada to find Delvac here. No response yet. Think I might just go with regular Mobil 1 synthetic as it seems OK to some people on here.

RallyJon

If you can fab a way of getting a little torque and about 100 rpms (like a crank) into one end, and something similar to resist a little torque on the other, you can test it in a vise. At 100 rpms, it should transmit enough torque to break your grip on the far side. Since Porsche apparently didn't publish kgf-m/rpm specs, not sure how much, but you should at least be able to tell if it's working at all.

Paul902

RallyJon,

somewhere in the archives there is a post including the torque spec. 11 ftlb on one side, to break the other, with input shaft fixed, IIRC. I've just pinged Chris Walrod regarding this whole issue. Was hoping not to have to take it out if I don't have to, but I was planning to change the oil and I do have 6 months of winter lay-up time, so no better time to take it out, I guess...

Garth S

Paul,
I spoke with the Esso Tech guy in TO this week ( and their appointed distributor here in NS). The Delvac is available .... in 20l pails @ ~$20/l .... however, despite previous comments favouring Mobil SHC/Delvac 75W-90, their comments were that this lube is lacking the additives for a LSD transaxle - so their recommendation was to stay with Mobil 1 75W-90.

I'm sure your LSD is still healthy, so Mobil 1 will keep it that way ....

Paul902

Good to know... I found Mobil 1 regular for $20/litre in 1 litre containers. Got 4, but need to pick up another for the front diff. I was going to propose to you that we get a shipment of SHC from the States (in previous thread someone posted a link) and split the cost of shipping/duty/brokerage, but if Esso says stick with the regular, that is good enough for me.

Happy travels,
Paul

PS How can you be sure my LSD is working??