Trans oil question
 

Hi guys, I have an '80 911 SC with a sticky 4th gear. They are all a bit tight but 4th is the worst. Have been told a quality synth oil would help. Any brands and weights would be appreciated. Cheers from Aussie-land.

RE: Trans oil question
 

Typically I use redline 75w-90, but a lot of guys use swepco.

RE: Trans oil question
 

Thanks Doc!

RE: Trans oil question
 

While I've got you Doc, I was going to try 20w 50 Mobil 1 next oil change but a tech from Mobil didn't recommend it. He said that it would more than likely make it burn oil becuase of the age and klms (200k or about 120k miles) and the detergents in the oil. What's your thoughts?
Cheers mate.

RE: Trans oil question
 

20w-50 is the standard oil you need to run in your car. Typically I don't run a synthetic in the older cars, because there is absoultely no need for it. The tolerances were not nearly as tight as they are today, and the engine has probably run standard oil in it for it's whole life, you will gain absolutely nothing by switching to a synthetic, and possibly will pick up some oil leaks if your old oil seals are starting to become hard. On the newer stuff that uses 20-50 (993's, etc), I usually use 15-50 when using a synthetic.

Keep in mind, Mobil 1 has changed their formula, and the oil contains less ZDDP's, which are additives which are shown to reduce engine wear. This has caused a huge uproar, and many people are switching away from M1 now. I have been using redline oil more and more, as those still have the additives, and there are other synthetics out there that still have the additives.

Hey PorscheDoc,
New member here with a question please. I recently picked up a 1997 Boxster with 72,000 miles. I have small oil leak and covers the rear bumper slightly when pushed a little. The car set up 3 years before I purchased it. Is a 97 considered "old" ? I purchased Mobil 1 Fully Synthetic oil to do my first oil change. If the leak is valve covers or rear main seal, would an additive to help be advised, or forbidden? I thought of adding something like Blue Devil for a short period before changing the oil to see if it would help with the leak, before taking to mechanic to make any repairs. Appreciate your help.
Fred