Synthetic vs. Conventional

[Pinoy911SC]

When I was in Hawaii, a well known Porsche Mechanic on the island of Oahu who did some work on my SC told me that syntetics were the way to go and he used only synthetic in his own 930. I use Castrol 20/50 now partly because I like changing oil every 2500-3000 miles and doing so frequently with synthetic makes no sense.

Anyway, I have two questions as I am about to store my car as I go off to my next duty station overseas in Korea.

1. Since my car will likely be started maybe one a month for the next 2-3 years, would it be better to store it with synthetic oil in the engine?

2. Once a motor has used synthetic oil, would it be wise to go back to conventional oils or should I remain with synthetic oils for the duration?

If synthetics are the way to go, I saw another post that Royal Purple, Swepco and Red Line were good to go with a good amount of the anti wear stuff already in it. Has anyone read anything on the Mobil1 15-50 oil? Okay that's the thrd question... Any advice on this will be appreciated.

Fred Ramirez
Fort Leavenworth, KS

[Por_sha911]

Fred, there are already a thousand posts about oil and everyone has a different opinion. Take some time and search. For starters, search for: ultimate motor oil.
As far as storage for 2-3 years is concerned, when the car is started it needs to be brought up to full operating temp and run for at least 15 minutes or so. Then, no matter what the mileage, change oil and filter once a year.
p.s. Thank you for your service to this country! Be safe and God bless.

[HarryD]

Fred,

With today's oil, the dino/synthetic argument is mostly academic.

More important is ensuring that the oil you use has enough of the antiwear additives and decent detergent package to ensure you do not see premature wear on your cams and other parts subject to high pressures.

Sadly, oil is no longer just oil. Due to Government and car maker pressures, the newer oils are now being formulated to not only lubricate your engine but also be "energy efficient", protect catalytic converters and allow for extended oil change intervals. These changes have been made at the expense of some lubrication needs of older engine that result in reduced engine longetivity.

You can read the Ultimate Motor Oil Thread or Why we hate CJ4/SM oils to get the full story.

Cliff notes go like this:

Originally Posted by HarryD

Older engines (pre-mid 90's) need high levels (around 1200 ppm plus correct level of detergents) of Zinc (Zn) and Phosphorus (P) to protect cams and other high pressure surfaces.

With the introduction of roller tappets in most engines by the mid-90's, this requirement is relaxed and Zn and P levels can be reduced. The EPA pressured API to reduce the Zn and P levels to (hopefully) extend the life of the catalytic converter which is poisoned by Zn and P. They complied.

Use 20W-50 or 15W-40 oil. Recommended brands, in no particular order, include:

Brad Penn 20W-50
Valvoline VR-1 20W-50
Kendall GT 20W-50
SWEPCO 15W-40

There are others as well.

Steve Weiner offers these thoughts:

Originally Posted by Steve@Rennsport

Hi,

Assuming that Porsche owners wish to stay informed and educated about an important topic, I've clipped a press release from JGibbs Racing about some changes coming in Sept.

Its no cause for panic or concern for people already using a good product in their 911's, but may be something to consider for those who haven't.

------------------

In 2004, API SM/GF-4 licensed oils hit the marketplace, and about 12 months later, articles and technical bulletins began to appear warning consumers of the risks of using low Zinc/Phosphorus API SM/GF-4 rated oils in flat tappet engines.

Today, the word is out – motor oils have changed. In 2010, passenger car engine oils change again, and heavy duty diesel trucks get catalytic converters.

This time, consider yourself forewarned.

API SN – ILSAC GF-5 licensed oil will hit the shelves in October of 2010, and this new oil specification places greater emphasis on protecting catalytic converters than previous oil standards. While this is good news for emissions, improved catalytic converter life has proven to be detrimental to flat-tappet camshaft life.

Another change associated with API SN/ILSAC GF-5 oils will be greater fuel economy performance. This improvement in fuel economy will be achieved by increased use of polymers called Viscosity Modifiers. These polymers help a “thin” oil act “thicker” under low stress conditions. While the liberal use of polymers helps improve fuel economy in passenger car engines, race engines produce shear stresses that can “tear” these polymers. When these polymers are sheared, your oil losses viscosity, and that can lead to increased wear.

More than ever before, engine builders, racers and hot rodders need to be aware that API rated products are “compromised” due to Passenger Car OEM requirements for improved catalytic converter life, fuel economy, and engine cleanliness.

To achieve these goals, oil marketers must reduce the Phosphorus, Sulfur and Zinc levels in their oils (.08), and they must use more polymers and aggressive detergents. While these changes are good for modern low rpm, overhead cam engines, older push rod engines and high RPM race engines need lubricants with higher levels of Phosphorus, Sulfur and Zinc as well as lower levels of polymers and detergents.

You don’t need to worry. You just need to choose the correct type of oil for your application.
----------------------------------------

Just keep using a product containing 1100-1200ppi of Zinc & Phosphorus and you'll be just fine.

[DanielDudley]

Originally Posted by Pinoy911SC

Has anyone read anything on the Mobil1 15-50 oil? Okay that's the thrd question... Any advice on this will be appreciated.

Fred Ramirez
Fort Leavenworth, KS

Mobil 1 15/50 Extended Performance is not good. Mobil One 15/50 High Performance is OK. Mobil One V Twin motorcycle oil is better.

[Pinoy911SC]

Joe / Harry,

Thanks both for the responses. As I looked at the other threads, ZDDP seems to be a topic of much discussion. From the list, there were several 15w / 40 motor oils listed. I've seen some of them on the shelves and if I recall correctly, they are recommended for diesel motors.

Anyway, I went into my garage to look at a container of castrol 15w/40 and it indeed had ZDDP. It was however an oil recommended for diesel motors. I've heard of good things about Shell Rotella. I think they carry 15W 40 in a synthetic formula. I'll check this week. If they do, I'll go with the Shell, add a shot of Lucas stabilizer and call it a day.

Daniel, thanks for the heads up on the Mobil 1 High Perf.

Thanks again for the response.

Fred

[HarryD]

Hi,

Steve Weiner has seen more stressed 911 engines apart than most of here due to his Race Shop.

Here are some of his recent (4/23/2010) thoughts on response to the Mobil 1 issue:

Originally Posted by 333pg333

I'm not sure if I'm imagining this but I look around various Porsche and Oil forums and there just seems to be some sort of blind allegiance to anything Mobil? I often direct them to this actual thread but usually don't get much of a reply. Especially the foreign sites. Perhaps there's an anti US sentiment, I don't know. I'm from Australia by the way. I've been checking out the BITOG site and searched under Porsche 944 turbos. Apart from the usual crap from people that don't actually own a flat tappet motorcar there is also some drivel by someone by the name of Doug Hillary who espouses using Delvac or other unsuitable oils.

Porsche 911 (air cooled) oil suggestions? - Bob Is The Oil Guy

On a UK site they won't even respond as they flog a 'Full synthetic' 0w/30 for just about any car.
Oil advice and recommendations (Opie Oils))

Lots of misleading info out there. Has anyone done an independent test on the 'new' M products that claim to have sufficient levels of ZDDP?

Originally Posted by Steve@Rennsport

Hi Patrick,

I've made the same observations and I think a large part of that is due to some excellent marketing by Mobil toward the OEM's such as Porsche A.G to get factory approval. Shell just did the same thing with Ferrari about a Pennzoil product. There is a lot of money at stake.

To address your question, I've not tested the SM-rated Mobil 1 15w-50, however I can tell you that these engines really need an oil that contains a minimum of 1200ppm of ZDDP to protect the cams and rockers (not to mention some other parts). Looking at that VOA report of Mobil 1's 5w-50, the ZDDP content is not quite what we want to see, despite their efforts to fortify this product with other friction-modifiers such as Boron & Moly.

Frankly, not that many people here have inspected the insides of a lot of engines to see the short & long-term effects of using the SM-rated oils in these engines so one needs to be prudent about what you read as well as one's choice of oils.

[Wil Ferch]

Shell Rotella-T 15W-40 is a mineral oil.

Shell Rotella 5W-40 is a synthetic, ....and they are dinking with the formulas as they offer a T6 variant and others...confusing. Caveat Emptor.

[HarryD]

Originally Posted by Pinoy911SC

Joe / Harry,

Thanks both for the responses. As I looked at the other threads, ZDDP seems to be a topic of much discussion. From the list, there were several 15w / 40 motor oils listed. I've seen some of them on the shelves and if I recall correctly, they are recommended for diesel motors.

Anyway, I went into my garage to look at a container of castrol 15w/40 and it indeed had ZDDP. It was however an oil recommended for diesel motors. I've heard of good things about Shell Rotella. I think they carry 15W 40 in a synthetic formula. I'll check this week. If they do, I'll go with the Shell, add a shot of Lucas stabilizer and call it a day.

Daniel, thanks for the heads up on the Mobil 1 High Perf.

Thanks again for the response.

Fred

Depending onthe product, you can look it up at Castrol web site here:

http://www.castrol.com/castrol/datasheetsearch.do

Be careful when you look at them and check the dates and which API Specs the report is based.

Shell has some good products. Again, be careful.

[tchanson]

Originally Posted by DanielDudley

Mobil 1 15/50 Extended Performance is not good. Mobil One 15/50 High Performance is OK. Mobil One V Twin motorcycle oil is better

Dan's reply above is the most admirably succinct and correct advice.





Mobil 1 15W50 in the silver cap:








Tim

[Kevin Stewart]

I am a hard core mobile one guy, UNTIL, yep you got it. I have mobile 1 in my mbz amg, 911, f350, wifes volvo, kids corrolla, and my outlaw oval track car, we have been running left over supply from a couple years ago, ran out this spring used 20/50 like always then started noticing car was running hotter tons of blow by, took it apart sludge in pan, broke a roller lifer, motor guy says yep gotta have the additives or the needle bearings go bad, he tells me this after we replaced the lifters and it took out the main bearing and broke a main cap. he said he sees the exact same issue with all motors that do not have true racing oil.

I went brad penn in the outlaw, probably gonna put itin my 911, not sure what to do with my amg, o and gonna put brad penn in the f350,

after 25 years and gallons and gallons i am done with them, Kevin

[kach22i]

Just buy a good 20/50 and add some ZDDP.

ZDDPlus Oil Additive - ZDDP for Classic Cars & Trucks


Wait until it goes on sale if you can.

[Por_sha911]

Fred; please go back and do some more reading. ZDDP is not the only issue. Many oil companies have been screwing around with the ZDDP and the additive package. I used Castrol GTX 20W50 but after 5k miles it ran out like water. Not so for Brad Penn. I know that there are other good oils beside Brad but you have to look at the whole picture. Right now you won't have that many miles between changes but you still need a quality additive package in your oil. Do your homework.