Synthetic v. Fossil
 

I can't recall what's been in my '92 C2 cab but i'm thinking of switching to synthetic.....if it's had normal oil in it, will it hurt to switch? it's got 38K miles on it.....other thoughts on syn. oil and recommended weights if you can.....THANKS!

You should read this thread in the 911 forum:

http://forums.pelicanparts.com/porsche-911-technical-forum/367300-ultimate-motor-oil-thread-why-we-hate-cj4-sm-oils.html

Regards,
David

Here's one vote for synthetic.

and another here.

The 964 doesn't like the thin 0w** or 5w**stuff though, 15w40 or 15w50 are good choices

The 964 was delivered from the factory with 5w-40 and I have yet to hear of any 964/993 related issues with 0w-40 (going on almost 10 years now that Porsche has been using it).

I've seen too many oil burning issues coincident w/ a change to 0w** and 5w** which go away when switched back to 15w**

I spoke with an authorized Porsche mechanic - then asked mutiple Porsche owners of late model series - and all said the transition to synthetic was a safe and recommended course. I have a 92 C2 as well with 47K miles. Did the oil change myself and the car runs superbly. I am more confident in the oils ability to keep its molecular strength. - BCC

BCC,
I have a '91 C2 with 47K miles and you just answered my question. I have always used synthetics in my cars with great results, but wondered about the new to me world of Porsche. I am looking forward to changing out the dinosour oil to synthetic. What brand do you and others use? What weight?

~jeff

Lot's of information on the main board recently.
Experts seem to be suggesting using Motorcycle Synthetic oil or if using regular oil Brad Penn or Swepco.
I just bought a case of Mobile 1 MXT 10-40 four stroke motorcycle oil for my 'new' 964 and will be changing once per year.
How cold does it get where you are? I wanted the protection of a 10w oil for the winter. The V-twin 20-50 is supposed to be good also. Both are 100% synthetic as fas as I know.

Do I have to flush engine with any sort of cleaner stuff before putting Synthetic Oil in engine ? The car I got seems used mineral.

Run Delo 400 Synthetic 15/40 in all of my vehicles including 2 911s. It's great stuff, still contains ZDDP, and is less expensive than you might think.

Nope.