Jerseybean

NJ-GT is semi local to me, hopefully he'll me at our next PCA meeting this week.

viperbob

When your shop put in the LWF, what did they do with the tranny oil? If it is Porsche factory still, then you will get gear rattle. If it was a perfomance shop and they used Swepco, Redline, et al, then it will rattle. WHile there is some variability from gearbox to gearbox if you use Mobil 1 75w-90 it will most likely go away (at least about 90% of it, which over the exhast can't be heard anyway). This gear rattle can be very loud in neutral as you describe, and also under heavy load like when accelerating from a low rpm in too high a gear and you lug the car.

I see this all the time with G50 gearboxes and LWFs installed else where, and changing the oil will most likely remove the issue. I will not install one myself without putting in Mobil 1 as I do not want an unhappy customer coming back. I know that Tom K. over on the TT board just had a LWF installed at the dealer with new Porsche fluid. WHen he drove up in my driveway I knew right away it was not Mobil 1 that was put it....

Jerseybean

I'm guessing it's got whatever the Porsche service manual tell them to put in. What kind of tranny oil does the factory normally put in? Isn't the GT3 gearbox a revised version of a 964 tranny, my 964 with LWF had swepco in it and didnt make as much noise.

viperbob

Yes the G50 is still kind of the same as your one from the 964 (well a few diffs like number of gears and such). Just try some Mobil 1 and see what it does. The oil is like $8-9 qt (4 qts) and it takes maybe a half hour to change. I have done numerous GT3s, and fixed other ones with LWFs and I had some very happy customers. I think you will be surprised... (I am also assuming that they did everything else correct).

Jerseybean

Bob
I did a little bit of research on renntech. Do you know if there's a difference between the Mobil 1 PTX (available to dealerships) and SCH (available everywhere).

http://www.renntech.org/forums/index...smission+fluid

Mr. C4

Hi Bob,

Is that Mobil 1 a particular gearbox oil or is it a very high viscousity standard mineral or synthetic oil?

Ciao,

AlanN

Sorry but that doesn't sound right to me, I have an RS and it doesn't sound like that!

viperbob

The standard Mobil 1 synthetic here in the states works great. Not sure what they put in the RS gearbox in Europe. I do know that I have changed out numerous LWFs on GT3s, and untold numbers on 993/964s. With anything but Mobil 1 I have found that the gearboxes turn into the noise buckets as you describe. With it, they quiet down tremendously. When new customers come in complaining of this with LWFs already installed, just switching gear oil will more than likely make them happy... Mobil 1 also has a friction modifyer, so it work well with LSD units with nothing else required.