Oil Recommendation

[Birmingham Bill]

I have no idea what oil was used in the car before I bought it (1990 911), therefore can you recommend what oil I should switch to? Also, will changing to a new oil cause me problems down the road? Thanks.

[IROC]

Pick your favorite and go with it. It's really not that critical. I'd probably use a 20W50 or something along those lines for our climate around here. I use Mobil1 15W50 and change it every 10000 km, but that's just me.

Mike

[RickM]

Here's a recommendation from an oil guy over on the PistonHeads site:

"Just bought a 1992 911 C4 3.6 with 66k miles on the clock."

"The correct grade for the car all year round use is 5w-40, this will prived good cold start and protect when hot, 5w-40 is usually fully synthetic, the 15w-40 is most likely to be a mineral oil to be honest you could do a lot better.

I would personally go for a porsche approved oil like the Silkolene Pro S range or the Motul.

You can top up with the Castrol as long as it is the same grade."


Here's an interesting comment:

"Look at true synthetics as they are more "shear" stable and therefore better for those times when you wish to do a bit of "spirited" driving. A synthetic should contain poly alpha olefin or ester, the best ones are a blend of the two."

[stlrj]

Factory fill is 0W40 Mobil 1

[jasonlee]

My mechanic, uses Lubri Moly(sp) 5W40 and it is manufactured by a divivsion of Porsche. He works on nothing but pre 90 p cars. Can't but it off the shelf, at least not here, so top up needs to be another brand of synthetic. Just my $0.02.