6ocyclehum

Just wondering.....I'm picking up an '86 951 on Saturday. I know the turbo can be hard on the oil. I read a 944 owner's manual on the net someone was nice enough to scan and post, and in the recommended oils section, it mentioned synthetics as a year round use oil and specified 10W-30 or 10W-40. I'm in a moderate climate (Kentucky- freezes in winter and summers are anywhere from 80 to the upper 90's F). I plan on using the car as a daily driver. Could end up tracking it one day, but wouldn't have a problem using a heavier oil for track duty. I'm not trying to start any kind of oil war, everyone has an opinion on oil, and many , many different climates. The reason I'd like to use syn 10W-30 is the fact I have 36 quarts of it. I'm always looking for oil deals, and found some really good ones. I've got a mixture of Valvoline and Pennzoil synthetic, which both should be good oils.

Mitch
99 996
86 951 (as of this Sat)

reno808

nobody

LFA951

Most in the summer use 20W/50, I use it year round here in Florida, Castrol and Valvoline are the most common names associated with our cars, up north they probably use 10W30 in the winter cold...

SamGrant951

Yup....in my Honda.

nitehawk951

Don't use anything from Pennzoil. Yes, everyone has their own opinion but I have seen the effects of long term use on the internals. It's not pretty. I use Royal Purple 20w50 or 15w40 (San Diego weather) because I believe it to be very high quality. Valvoline and Castrol are great too. But I think you should use 10w30 for whatever oil you choose.

333pg333

Unless you live in the Tundra, don't even think of using something of that weight.

6ocyclehum

Pennzoil makes good oil (at least they used to), I used it for 10 years in 472 cubic inch Cadillac engine and the engine was totally spotless, ran perfect, looked brand new. I took good care of it and changed every 3000 or 4 months, whichever came first. Not my first choice, but I usually get whatever name brand is on sale. I think most of today's name brand oil is pretty good.
I'm not real suprised on the replies, I looked at the archives first, and saw most use some type of 50 weight oil. 20-50 is some VERY thick oil, I used it in some of my Jags over the years, seemed OK (and the Jags all burned/leaked oil, so the 20/50 helped the consumption). However, I was concerned about cold start flow with oil that heavy. I do remember hearing a bit of bearing noise on one of them using 20-50. My last Jag was a 95 supercharged XJR and I ran 10-30 in it, did fine, but it did consume it quicker than say, 15/40.
The Porsche manual states 10-30 synthetic is acceptable for the 944. I was just curious if anyone here had ever used it. I got 10-30 full synthetic Valvoline for $0.50 a quart!!!!! Cheaper than crude!

M758

Wrong,
The guy that just spun a rod bearing.... Sadly have seen it happen.

azbanks

oil=cheap
rebuild=not cheap

Is the little money you save on the wrong oil going to add up to enough to cover the engine rebuild?

6ocyclehum

From what I've been reading on the archives here, there have been plenty of spun bearings and engine rebuilds with people using 50 weight oils also. I'm talking daily driving, not the track.
I have other cars I can use the 10-30 in. I was thinking of "treating" the 944 to my "synthetic reserves", which perform well under extreme heat, and have a longer oil change interval. I don't mind getting a heavier oil for the 944, if that's what's needed. 20W seems too thick for my climate (Phoenix , I can understand, used to live there). Maybe some 10-50 syn, or 15/50 might work for my climate.
I've also seen in the archives that the reduced zinc content in current oil is of some concern with the older P-engines. Do you guys like the diesel stuff, that's supposed to have the zinc content of the older oils (Rotella, Delo, etc)?

Renn 951

I believe the zinc issue really applies to the older air cooled engines. The climate in my area is similar to Kentucky, and I've been using Mobil 1 15W-50 exclusively for seven years and about 30K miles, much of that on the track. The car is by no means a daily driver and doesn't see a lot of use in the winter, but I still start it up regularly with no problems in the cold temps of winter and put some miles on it. The previous owner also used Mobil 1 15W-50. I think 15W-50 would be a good choice for you for your environment and the intended use of the car. If you REALLY want to use your 10W-30, I'd recommend only using it Dec thru Feb, and then going with 15W-50 for the rest of the year.

You also should consider what the previous owner used in the car. Switching to a lighter weight synthetic can sometimes result in a lot of oil leaks if the car has been run on heavier non-synth oils over its life.

DrZ1

I like the Rotella T 15w-40.

Steve

KuHL 951

10W-40 M1 dropped my oil pressure a full 1.5 bar at idle after a hot run compared to 20W-50; 10W-30 would have killed it. I know there is a lot of talk about the Porsche approved Euro Mobile 1 0W-40 but in my climate I'm just not switching after 5 years of success with 20W-50. I use Valvoline Racing VR-1 20W-50 now as it has plenty of ZDDP content and has performed in the hottest weather which we have plenty of. YMMV but Phoenix

David Floyd

Happy reading


http://www.lnengineering.com/oil.html

David Floyd

[QUOTE=KuHL 951;5539782]10W- I use Valvoline Racing VR-1 20W-50 now as it has plenty of ZDDP content /QUOTE]

Not any more, read in the link above.