Hey ya'll. I'm finally restoring my old 914-6 I've had for 35 years. Sorry, I got sidetracked by a few 911's and a 944. I've got the engine done and am considering installing a LSD in the trans. I'd like your recommendations for a LSD for street and the rare autocross? But my main question is for gear lube recommendations, both with and without LSD?

To me you only need a LSD if you race a lot, very high HP or drive in the snow often.

IIRC the Quafe LSD is the best bang for the buck.

Years ago, Swepco was the best gear oil for porsche transmissions.
Not sure if there is something better now.

Swepco

Guard and Quaiffe both make great products. I would recommend a Torque biasing differential over an LSD for your stated street / autocross purposes.

Swepco is ok and I swear by their 101 grease, but personally I don't believe the hype on the gear oil.
To me it's just average gear oil with a pretty blue dye and a high price tag. I have two jugs of it gathering dust on a shelf in the shop.

To me Kendall has always been a far superior gear oil, try Kendall NS-MP Gear Lube.

When did they add blue dye? (Yes, My SWEPCO gear oil is that old!)

Don't know, over 10 years.
One thing I have been doing is adding 1/2 quart swepco to my gear oil so I can easily see if an oil leak is tranny or engine.

I've had good luck with Sta-Lube in 901 ZF LSD equipped transmissions:

Click to view attachment

You can get it online or at your local NAPA.

Used Swepco for may years in 911/914...good oil and the best for finding leaks...always a little purple spot under any transmission
using it....whether old or just rebuilt.... No weeping problems with the Sta-Lube

Used Redline in the race gear boxes....never a problem on hard worked 901 or 915 transmissions

Guard Transmission makes the best limited-slip diffs. For the track, the friction-based LSD is preferred. For autoX or the street, the torque-biasing one is generally preferred.

Be prepared to pay for the best if you want the best. GT isn't cheap.

--DD