rwodabek

I'm having a bit of trouble finding 15w-50 in stores. What's the difference with 5w-50? Is it a good substitute?

mikew968

Amsoil 20w-50 is available and works great.


Mike

rmdsolutions

Try Wal-Mart that is where I get mine

Greimann

Living in Canada, in the winter, you definitely want the 5W stuff. 0W if you can find it.

The first number, designated with the W, is the indication of the ability to flow at cold start. That is the critical situation. The second number is the viscosity at operating temperature. Since the winter in Canada will keep the engine right at thermostat temperature, a 0W-40 is more appropriate. In southern climates, 15W is good to about freezing. Any colder, you want 5W or 0W.

Kit_Chris

Are you driving in winter? If so stick to 5W50, readily available by M1 everywhere. Higher viscosity oil tends to sustain heat much better and retain its properties in extreme temperatures, tuned turbo engines should run at least 15W50, which is as far as I know the highest viscosity oil Mobile 1 makes for automotive applications, although I remember reading somehwere that they were re-introducing 20W50 although this may be the motorcycle application Mobile oil. In any case, a I see little benefit in running higher viscosity than say 10W in a stock Porsche engine; some say higher viscosity reduces power somewhat since the oil pump must work harder, but you'd need a very sensitive backside to notice that.

If you choose Mobile 1 15W50, the only place I could find it was South of the border, K-Mart has it for 4$ a quart, which is about half the canadian price! Stack up on your next visit down South!

Regards,
Bruckner

Luis de Prat

FWIW, we have Mobil1 5W-50 "Rally Formula" here in Europe and it was recommended by the AMAG Porsche Center that serviced my 951 when I bought it in Switzerland in 2000. I'd say Switzerland is on par with Canada for cold winters. That's 7 years and counting.

I think 0W-40 is too thin for the tolerances our engines were built with.

rwodabek

Yes, I drive it year round. I ended up picking up the 5w-50 after all. Can I use this all year round? Or is it really better for the cold weather?

Luis de Prat

The head mechanic at the Swiss AMAG Porsche center I mentioned recommended it for year round use.