Originally Posted by
curtisr
Gentlemen, please!
Engine oil grade is a function of an ambient temperature range in which the car operates. Chrysler has chosen to keep things simple by making a singular recommendation: 0W40. So, too, nowadays Porsche does the same thing; however, if you think that owners of late-model 911s restrict themselves to that single suggestion you are mistaken. At least not by those who drive the cars on the track.
Consider this ACTUAL oil chart for a Porsche 928 (which I own) by way of example.
Yes, Porsche is saying that it is perfectly acceptable to use 5W20 up to and including a 20W50 but you must govern yourself according to the temperature table. Clearly the oil one would choose for use in Finland might differ from the deserts of the United Arab Emirates. My point is using 5W40 or 5W50 is perfectly acceptable in North America.
I may get "blown off this page" as you say but at least I know I won't be blowing up my motor come the hot days of summer if I use a 5W50or 10W... Perhaps as a final thought (for me anyways) one might wonder if these light weight oils are for preserving longevity or upping the manufacturers CAFE numbers...
For more fun visit:
https://bobistheoilguy.com/motor-oil-101/
I NEVER said only use Mobil1 0W-40, where you got that from is amazing. I also suggest you not compare Porsche motors to MB motors, it is apples and oranges. These new motors are much tighter by design, and the oils were designed to support them for a long life. It is not the old way of 'oils are oils' anymore. I may be wrong but I believe Porsche made only ONE motor for MB (a 5 cyl diesel, according to a brief research). You can put whatever you want to in your motor BUT my LPW may be invalidated if I put anything else in it but 229.3 or 229.5 oils. Also, the FSS system requires this synthetic 'standard' of oil so it works as designed.
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