Mixing 0w40 and 10w40 to make 5w40?

Hey guys! First post for me! Just bought an ' 06 Cayman S two weeks ago. Been reading a bunch of threads on oil and how really 0w40 is not ideal for protection. However, finding 5w40 or 5w50 is a pain, and when you can it's EXPENSIVE. So, I saw you can get Mobil 1 5qt jugs of 0w40 and 10w40 for ~$22 ea at Walmart... So, what if you were to mix the two? Would you effectively make Mobil 1 5w40? Thanks! Eric

Lmgtfy

welcome Eric Try reading this https://www.mobiloil.com/USA-English/MotorOil/Car_Care/AskMobil/Mixing_Motor_Oil_Viscosity.aspx If it were me, I'd just follow what the manual says. Where have you read that 0 - 40w is bad for 2006 Cayman S cars since that is exactly what Porsche says to use?

ameutch, thanks for the warm welcome. chows4us, I've actually read that before... But, the answer from the Mobil peeps is a little less than helpful. As for not using 0w40.... http://www.planet-9.com/987-cayman-...7-cayman-boxster-competition/51240-oil-track-my-experience-mobil-1-5w-50-a.html http://www.planet-9.com/987-cayman-...n-boxster-service-tech/83525-porsche-approved-engine-oils-can-we-cut-chase.html and others... But, of course, search enough on the internet and you'll find something to prove you right/wrong, no matter what it is. Am I over-thinking this whole thing?

Eric, assuming you've read all the research you have done, can you explain in your own words why you've concluded the 0-W40 is no good? BTW, I can't tell from the Tapatalk posting where you are operating the car, or if you think that would make a difference. Sent from my iPad using Tapatalk

The first thread was about tracking the car. I'll leave it to the track junkies to answer that as they can answer better than me. If you do a lot of track days, they will have the expertise and can speak up. Otherwise, yeah, I think you are over thinking it. I've had a 06 987CS for 8 years, always used Mobil 1 0 - 40w, never an issue. And all boxer engines will burn a little oil.

Let me google that for you

Just stick to 0W40 if that's what the manual says ...

Lot of internet misinformation and hysteria on this out there. There are numerous Porsche recommended oils including 0w-40, 5w-40, and 5w-50. Most are 0w-40. If you have a street car, 0w-40 is perfectly fine. And there are 5w-40 oils that are not crazy expensive nor hard to get. Castrol for example. If tracking aggressively in hot weather, 5w-50 has definite benefits as it retains protective properties into hotter oil temps. However, it's nonsense that 0w-40 is "not good" for our engines for general usage. Yes, I understand that certain well-known shops say to use 5w-40 and other special oils.

Are people still posting that old joke? I thought it went out with the Arc.

If you want 5-40, just get Castrol . Its A40 spec, porsche approved and goes on sale all the time.

And, of course, there are those articles in the trade rags that actually talk about using the 0 viscosity as a bit more protection for the IMS ....better penetration and all that....... just sayin'.

If the car won't see the track - using M1 0w40 is just fine. I only use M1 5w50 (and posted about it) because of extended periods of elevated oil temps at the track. To further address this, I'm also using a low-temp t-stat and 3rd radiator...both of which I'd also recommend.

I decided to return the 10w40 and picked up a few quarts of M1 5w50 online. I figure I'll use the 5qt jug of 0w40 and finish off the rest of the oil change with the 5w50. That way I am only using Porsche Approved oils, I have a little extra protection for when I have fun, and I split the difference cost-wise. Thanks everyone for the input.

I'm also confused with the oil ratings..I live in Africa, Nigeria where the temperature goes as high as 33 / 37 degrees is it okay I use 10w 40 cos atimes the engine feels so hot..takes like a whole day to cool down,. I always have to put the AC on to make the engine temp normal