Newbie Oil Help

[Spun01]

Hello. I am a happy new owner of a '90 964 C2 w 120344 miles. Being a newbie I just wanted to gather some info/advice on engine oil brand and type to use. My engine is very clean and thankfully no oil leaks and I would like to keep it that way, so any info would be greatly appreciated. Also, I am using my C2 as a daily driver, mostly freeway about 30 miles round trip, if that helps any. I also read about oil pressure and oil level and their gauge readings. What should I be seeing on a regular basis? In any case, I would greatly appreciate any feedback to help me out. Thanks.

[dmwallace]

Spun01,

The official oil thread has lots of great info at
Ultimate Motor Oil Thread or Why we hate CJ4/SM oils

If you go through the thread you will see that the experts generally recommend both Brad Penn and Swepco oils as two manufacturers having the right additive package for our engines. Brad Penn is available in a 20w-50; Swepco is available as a 15w-40. Our host sells the Swepco; oil guru Charles Navarro sells the Brad Penn at www.LNengineering.com.

Re. oil level - your owners manual and the experts here all state that you check the oil based on the dipstick when the car is on a level surface and the engine is at operating temperature (oil temp gauge at 8:00).

Congratulations on your purchase and welcome to the forum. You should post picture of your new ride!

Regards,
David

[lucittm]

Al,
I was in the same quandary a year ago with my 1991 964. I did some research and tried to remain objective. I always came back to Mobil 1. Here's why:
1. It is a proven product.
2. Porsche put it in the car on the assembly line and recommends it.
3. I use it in my other vehicles without any problems
4. I used to race motorcycles, we burned up (bearings and pistons) some engines on petroleum, we never had a problem with castor oil or synthetics.
5. Synthetic oil really never wears out, if you could filter it clean, you could probable put it back in and run it for another 5-10K miles. Some of the additives go away over time, but I think that is subjective and also based on how the car is used.

Anyway, I run Mobil 1 10W-30 in the winter and 15W-50 in the summer. My car has 60K miles on it but it is a daily driver now, over 100 miles a day.

It would be good to know what oil was used during the car's history, do you have the records? Some people say that with over 100K miles, switching to synthetic now won't make much of a difference. I disagree.

It costs a bit more, but if you buy it in the 5 quart jugs, it isn't so bad. They sell a lot of it and it is priced higher because that is what the market will bear.

Thanks,
Mark

[cjoenck]

OK, I think everyone should read this first

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

The reason why a "modern" oil might not work as well for an air/oil cooled 964 is that modern engines are designed very differently with very different tolerance etc. the an engine designed 17 years ago.

I personally have seen a difference in using Swepco 306 compared to Mobil 1.

Just make sure, you do not overfill - ask me how I know

[kang]

Originally Posted by cjoenck

OK, I think everyone should read this first

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

The reason why a "modern" oil might not work as well for an air/oil cooled 964 is that modern engines are designed very differently with very different tolerance etc. the an engine designed 17 years ago.

I personally have seen a difference in using Swepco 306 compared to Mobil 1.

Just make sure, you do not overfill - ask me how I know

Personally, I don’t buy the argument that these lower Zn and P levels in newer oils are causing engine wear. The newer oils meet more stringent engine wear requirements than older oils do. Focusing on one component only, ZDDP, doesn’t show the whole picture. ZDDP is what they’ve been using for 20 or 30 years, don’t you think they could have come up with a replacement in that time?

Doing regular oil/filter changes is, by far, more important than what oil you choose. I use M1 0W-40, the factory recommended oil, and I change it every 5,000 miles.

[bleachii]

Originally Posted by cjoenck

OK, I think everyone should read this first

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

The reason why a "modern" oil might not work as well for an air/oil cooled 964 is that modern engines are designed very differently with very different tolerance etc. the an engine designed 17 years ago.

I personally have seen a difference in using Swepco 306 compared to Mobil 1.

Just make sure, you do not overfill - ask me how I know

Out of curiosity....what differences have you seen?

[lucittm]

cjoenck,
Personal oil preferences are like religion, or maybe like the PC vs. Mac debate. Everyone thinks their personal insight or experience is the best for the un-initiated masses.

It is very difficult to prove that any specific engine oil "caused" an engine to malfunction, wear out, burn up, or "blow-up". (Think about the lack of lawsuits here) The exception is my Mom. She drove a VW bus for about 3 years and never checked the oil. One day it didn't want to start, it was towed to the German Auto and the mechanic said the crankcase was dry, not even a film of oil was in the engine. He replace a connecting rod bearing and filled it with oil. It ran for another 15 years. But I digress...

Most engine difficulties can be traced to:
1. Contamination (water, dirt, sludge, or metal dust/chips from normal wear)
2. Mechanical problems such as bearings that are incorrect, over tightened, overly loose, over stressed (think drag strip loading), or a complete failure of a part like a rod bolt (no oil involved)
3. Overheating. All oils will eventually fail to lubricate if they get hot enough

The contamination interferes with the oils ability to prevent metal-to-metal contact. The overly tight/loose bearings prevents the oil from creating that cushion effect due the fluid dynamics of occupying the space created by the proper gap/clearance present in all engines. The overheating destroys the visco-elastic property of the oil and it literally runs out of the gap, allowing full metal-to-metal contact (for a very short period of time, then these two pieces become one).

I crack up when someone shows a picture of a piston blown in half across the pin holes and says that he had the wrong oil in his car. In fact, the guy just installed a 36 psi waste gate and a K27 turbo in his 10:1 compression engine and decided to see how high the RPMs would go. The piston flies off the connecting rod due to Newton's second law of mass, motion, and change in velocity. Of course, oil is pouring out and so the guy blames the oil.

Here is a list of the manufacturers/models that have Mobil 1 oil put in the vehicle on the assembly line:

Acura RDX

Aston Martin

All Bentley Vehicles

All Cadillac Vehicles

Chevrolet Corvette C6 and Z06

Chevrolet TrailBlazer SS

Chrysler 300C SRT-8

Cobalt SS S/C Coupe

Dodge Caliber SRT-4, Charger SRT-8, and Magnum SRT-8

Jeep Cherokee SRT-8

Mercedes-Benz AMG Vehicles

Mercedes SLR

Mitsubishi Evolution

Pontiac Solstice GXP

All Porsche Vehicles

Saturn Ion Red Line and Saturn Sky Red Line

Viper SRT-10


I cannot think of any other oil maker/refiner that can make a similar claim. Not Amsoil, Pennsoil, Brad Penn, Swepco, Kendall, Castrol, Vavoline, Havoline, etc. Also, I automatically discount any claim made by the retailer, wholesaler, or maker of a product, so the guys at LN Engineering want to sell more of the oil they carry. Nothing wrong with that, I'm just not going to buy it, that's all. I don't care if it's green, red, or smells minty fresh.

Until then, I will continue to use Mobil 1. In this case, "to each his own" is a good way to go. Hey, I'm not a petroleum engineer, but I did stay at a Howard Johnson's a few years back. Please don't rebuke me, these are my own opinions, YMMV, no fiduciary relationship, etc...

Thanks,
Mark

[dan79brooklyn]

I'm using Mobil 1 MXT 10-40 (synthetic motorcycle oil) It's got lots of additives and is expensive so it must be good. Reccomended by the oil guys too. No leaks that I've noticed.

[cjoenck]

All really good points. I agree, there probably is no absolute answer until we look at scientific research, i.e. oil analysis, engine wear over a long period of time. Until then, it is probably as much in the eye of the beholder

I am not a mechanical engineer, nor do I have a chemistry degree or any financial interest in any oil company.

I did notice better cold start, quieter engine run, slightly better fuel economy - however a bit to early to tell.

[aigel]

The best oil is the stuff you change on a regular basis. In a moderate climate 15W50 is recommended. I use Mobil1, since it is readily available locally. Oil threads are always terrible. There are a lot of people swearing by their stuff. I think it is overrated. Technically any modern oil in the right viscosity will be ok to use.

George

[amr89c4]

Quote...."Here is a list of the manufacturers/models that have Mobil 1 oil put in the vehicle on the assembly line:

Acura RDX

Aston Martin

All Bentley Vehicles

All Cadillac Vehicles

Chevrolet Corvette C6 and Z06

Chevrolet TrailBlazer SS

Chrysler 300C SRT-8

Cobalt SS S/C Coupe

Dodge Caliber SRT-4, Charger SRT-8, and Magnum SRT-8

Jeep Cherokee SRT-8

Mercedes-Benz AMG Vehicles

Mercedes SLR

Mitsubishi Evolution

Pontiac Solstice GXP

All Porsche Vehicles

Saturn Ion Red Line and Saturn Sky Red Line

Viper SRT-10

I'm no petroleum engineer either, but I like a good debateand there are lots of folks tossing in their jingle, so I might as well stir the pot, too.

So, just as an observation, how many of those NEW cars run flat tappet, air/oil cooled engines???? Hmmm, I didn't see any new flat tappet Harley Davidsons in that list, either. I recall that when our older cars were built, the oils that Porsche put in the engines had high zinc content. It seems the zinc reduction began about two years ago or so and M1 was one of the first to pull out the zinc content. I recall a lot of folks that are smarter than me jumped ship that were perfectly happy with M1 until then. So this is not a new development. Me, I'll take the zinc package, thank you. Better safe than sorry. While I use Brad Penn in the '89 964, I'll admit that I use and recommend M1 in the '97 roller lifter BMW. But they are two distinctly different animals.

On another note, I don't subscribe to the dino oil "wears out" argument either. Yes, their additive packages lose their properties and effectiveness over time, temperature, humidity and pressure, but the oil carrier just gets dirty and therein lies the problem with dino and synthetic oils alike.

Its just another opinion, but I do agree that frequent oil changes can offset oil issues and frankly, I worry more about the lack of use of both my Porsche and BMW causing film retention issues and oil contamination (acids and water), more than I do the actual wear process. Infrequent use and periods of storage with contaminated oil are of greater concern than oil failure in extreme (not abusive) conditions.

[dmwallace]

+1 on amr89c4's comments

I'm no expert but have been following the oil discussion for the last several months and have found that the information provided is worth paying attention to (for me). In my 993 I switched to Swepco 306 15w-40 after acquiring it last fall and will be using Swepco again for the spring oil change. I noticed that Mr. Navarro (one of the oil gurus) recently posted that he is using a blend of 2 multi-weight Brad Penn oils in his personal car (believe it was 10w-30 and 20w-50) so I will be looking for his UOA to see if that is worth considering.

I did use Brad Penn on my former car ('89 3.2) and noticed reduced smoke on start-up, quieter idle, and also freer reving in the upper range.

Regards,
David

[lucittm]

Based on some recent posts I did a little research. It seems many of us may be right. Here is a great link I found:
http://www.mobiloil.com/USA-English/MotorOil/Files/Mobil_1_Product_Guide.pdf

It seems that according to this chart, Mobil 1 0W-40 is recommended by Porsche and has 1000ppm ZDDP.

Also, the Mobil 1 Extended Performance in 15W-50 has 1200ppm of ZDDP and it is the highest next to the motorcycle oils that have 1600ppm. The 15W-50 is recommended for "flat tappet" and "racing" applications.

I also see the Mobil 1 10W-30 that I am using, has been affected by the ILSAC GF-4 specification and has 800ppm ZDDP. So, I am looking to change my oil soon.

I hear they scrape the tar off of the roads in Milwaukee and put it into new Harley Davidsons.

Thanks,
Mark