hosrom_951

Here is the oil grade chart from the 944 owner's manual:



As you can see, the manual indicates that the 15w-40 and the 20w-50 oil grades are recommended for weather conditions exceeding 40C (102F).

Here is the thing, Mobil 1 15w-50 is NOT available in the Middle East anymore. ONLY the 0w-40grade is available, which is crap since we never get 0C in winters nor do we get a max of 40C in summer (110+F).

Now, i am changing brands to Total oil, since they have the 15w-40 oil grade, but as a SEMI-synthetic grade. This is fine yes?

Secondly, the manual shows that the 10w-50 grade is best used up to 35C weather conditions. Total claims that THEIR 10w-50 grade is BETTER than the 15w-50 grade (their product), but the manual states otherwise..........

Should i go for the 15w-50 grade semi-synthetic or should i go for the 10w-50 FULLY synthetic grade?? (both from Total).

DDP

I wish I had as much time as you have to think that much about that kinda stuff, lol.

Sorry couldn't resist.

GlenL

Personally, I'd go with the thickest fully synthetic I could find.

The complicating factor is that oils have gotten better over time. Also, oil viscosity really isn't a measure of how well it lubricates. Thick oil does produce higher pressures especially at higher temperatures. Thick oil also become more important as engine wear.

So, even though thinner oils provide good lubrication, our old cars need thicker oil. In your environment, the thick stuff is additionally valuable.

Manning

It will take 10 bottles of the semi-synthetic stuff to equal one bottle of Total

Clint

I would go back a step and reconsider the 0W40. You are looking at a guide that was suggested with oil quality in the 80s, Porsche has since changed the suggested requirements. I lost the document, but I think it was in 2002, but when I read it 0W40 was now the suggested synthetic oil.

bearone

either way, 20w50

87951

944CS

0w-40 is meant for the 996's and newer, it will not provide the correct oil pressure for 944's

mgmarsh39

why pay for oil? i just put water in there!!!

haha

Macfreak007

aggred, I have tried this, not a good idea in my opinion, I still blame this partly for the fact that my motor spun a rod bearing...

hosrom_951

When 15w-50 was available from Mobil 1, i got 3bar oil pressure when fully warmed up, 2 bar driving crazy in 130+F last summer, which is GOOD!

Now, i use 0w-40, i get 2.0-1.9bar when fully warm, and 1bar when driving hard, and that is in 110F weather.......see the pattern?

My concern was between a FULLY synthetic 10w-50 from Total, who claim it is the best product they have, and their own 15w-50 SEMI-synthetic oil.

Fully synthetic is better than semi synthetic right? BUT the manual indicates that the 15w-50 is better suited to 40+C weather, than the 10w-50. Total claims the opposite..........so should i go for the 10w-50 FULLY synthetic or the 15w-50 SEMI synthetic?

hammerwerfer

My 951 was owned by a Porsche Service manager for the past 17 years and always serviced at his dealership. It has the 0W-40 Mobil One as used by Porsche in it and the pressure is fine.

I use about 1 litre every 750km of rather strenuous driving.

GlenL

Go full synthetic. When going to the lower weights, look at the minimum temps of the operating ranges. It's not getting close to 0C there, is it?

And yes, Porsche has changed the suggested weights based on improved quality. If my car was new, or low mileage, I'd be using 0w30. I'll go 5w40 in the Winter, but then 0C is a warm day in these parts.

hosrom_951

Okay, i am settling for 10w-50 FULLY synthetic over 15w-40 SEMI synthetic then.........

The coldest we got in winter was 10C and now we have 45C summers, so the 10w-50 seems to win. But like i said, the manual states the opposite, perhaps with today's oils, the 10w-50 is more better than back in the 80's.