Quote:
Originally Posted by Schulisco
On a tight engine which has been operated all the time with synthetic oil - yes, they will work and on them I wouldn't expect additional leaks. The OP asked for experiences in switching from synthetic to conventional oil due to availabiliy issues. There I personally expect additional leaks as Ivan also suspects.
No. Not all Porsche oils are synthetic!
Yes, Porsche provides own oils, and they're pretty good oils, as always to be expected. BUT: The 20W50 is a conventional mild alloyed engine oil, the 10W60 is a synthetic engine oil! Porsche recommends the 20W50 for the 911 engines up to 2.7l, from 3.0l on the recommend the 10W60.
https://www.porsche.com/usa/accessoriesandservices/classic/motoroil-faq/
https://www.porsche.com/stories/innovation/what-is-the-best-engine-oil/
I consider following the original specs Porsche did in the manuals:
The older an engine is or the more mileage an engine has, the more I tend to use a conventional all mineral-based only oil. Also it depends what previous owners filled in.
The more modern an engine is or it already an overhaul in the last years the more safe I feel with synthetic oils. |
True the 20W50 is dino oil but that's only for pre-1977 cars. The 10W60, 10W50, and 5W50 oils are all synthetic. OP has a 1986 car - Porsche recommends synthetic. Porsche doesn't make a distinction between what oils had historically been used in the engines.
I've been running High Performance Lubricants Bad Ass Racing Oil 10w60 in my '87 930. I'll tell you I've never had leaks anywhere close to as bad as after the last shop filled it with Brad Penn 15w40 (which also was NEVER the viscosity spec for a 930 engine so who knows what they were even thinking?).
Porsche 10w-60:
https://bobistheoilguy.com/forums/threads/voa-porsche-classic-10w60.253341/
HPL Bad Ass 5w-30 (would expect similar from the 10w-60):
https://bobistheoilguy.com/forums/threads/high-performance-lubricants-bas-5w-30-racing-oil-voa.310686/