1999Porsche911

One of the drawbacks of a purely synthetic oil is the inability to maintain the flexability of various seals in the engine. Although additives have been improved over the years. they still have not found a combination of seal material and additive that will work. A dyno oil (regular mineral motor oil) helps to keep the seals properly conditioned and flexable. This is why, 9 out of 10 times, filling your crankcase with dyno oil when you have a small seal leak, will completely eliminate the leak, as it restores the seal, making it flexable and reversing the shrinkage.

My recommendation would be to use the 15W50 in Connecticut in the off winter months. The Mobil 15W50 Extended Performance still has the correct level of cleaners. Many of the other grades have reduced them. Elf is also a great oil as is Castrol Syntec and many others.

If you are currently running 0W40 and burning oil, in many cases you'll see an immediate reduction in oil usage as well as smoother idle and quicker engine response using the 15W50. With 0W40 oil, your hot engine is unable to maintain adequate oil pressure (as your gauge will tell you) to maintain safe clearances between and crank and IMS bearings. Using 15W50, pressure is no longer a problem.

There are many sides to the oil deabte and it boils down to what you decide based on looking at all sides of the debate. Many people just accept what Porsche suggests, but many of those are also the ones that accept that it is normal and good for the engine to burn a quart of oil every 500 miles and that it is normal not to be able to shift into 1st gear easily, that there is no need to change your motor oil more frequently than every 20,000 miles, etc, etc. I think they refer to these problems as the "character" of a Porsche. I call it "denial".

Common sense would dictate that if someone is burning oil using a specific brand or weight of oil, they would try an alternative?

1999Porsche911

Virgin Olive Oil.

Tool Pants

The oldest Porsche approved oil list I have is dated March 17, 2000.

There is a convernional mineral oil on the list. Exxon Superflow 15W-40.

And, oh my god, Mobil 1 15W-50 synthetic is also on the list.

Extra virgin olive oil. Nothing but the best for my Boxstir.

1999Porsche911

I read that the Ferrari owners use the same Olive Oil but add a little red vinigar to it.

redridge

I use 15w-40 as 1999 susggested on my 2000 SC, I like the extra oil pressure it gives.

JasonAndreas

Use any oil on THIS list. Adding non-synthetic won't hurt you but it also won't do anything, especially for your crankcase seal.

1999Porsche911

Wrong! This has been proven over and over and over again. Seals remain more flexable and do not shrink and dry out as much with dyno oil. Can't argue against fact. Some synthetics use more seal conditioners than others.

Since so many of you always refer to web pages as FACT, here is one for you.


http://www.auto-rx.com/pages/faqs_old.html#U13


There are dozens and dozens of other that also state that non synthetic oil helps return the plyability of seals. What do you think the main ingredient in seal conditioner is?

marlinspike

It's in the Panerama archives if you look through there, it was cool out (IIRC around 50F or so) and the lifters wouldn't pressurise because the oil was too thick to even get to them.

wrljet

Current no conventional oils are recommended by the TSBs.

JasonAndreas

What material is the main crankcase seal made from? And what material is impervious to the seal swelling conditioners/additives/agents that you were telling people would help prevent RMS leaks, if only they poured in a bottle with each oil change?

What year did Porsche start using synthetic oils? Do you really think the german engineers @ PAG chose the gasket and sealing materials used in the M96 without understanding the effects that the synthetic oils (that they were specifying) would have on them?

BruceP

I don't know much about this stuff, but I have to agree with the logic of this point. I just can't buy into any advice on a message board that's based on the assumption that a) Porsche are idiots, or b) Porsche is engaged in a fiendish conspiracy, the motives for which are too arcane for mere mortals to understand.

swmrdrn

If you want to fight about oil then here is the forum for you http://www.bobistheoilguy.com/

Doug Hillary

Hi,
IMHO the misinformation on lubricants and lubrication that has been Posted by 1999Porsche911 over several threads and several months needs to be carefully analysed before acting upon it. Most of his information can be quickly dismissed by the supporting facts. He never seems to be able to supply any to support his own theories!

Two follow;
1 - "Actually, it is the opposite. Lifters have more problems at startup with 0W40 that with a 15W50"

And,

2 - "With 0W40 oil, your hot engine is unable to maintain adequate oil pressure (as your gauge will tell you) to maintain safe clearances between and crank and IMS bearings"

Sadly he has a very limited understanding of fluid dynamics and lubricants/lubrication in general! And many others have pointed this out to him!

I suggest anybody tempted to believe his Posts should at the very least consult an Oil Company's Lubricants Engineer or their Chemist first. Sales people won't do. Many very competent people here on Rennlist and elsewhere have called his bluff before!!!

A much simpler way of course is to believe what the Porsche Factory's engine Designers and Engineers have to say. Following their Technical Service Bulletins (TSBs) on lubricants (which always supercede Handbook data) and are produced in the light of field performance of the engines in service is the best advice you can get

For those persons not already aware of it, Porsche first filled with synthetics in MY1992 - an SAE30 viscosity (10w-30) at first and then with a SAE40 viscosity (5w-40). Both were Shell lubricants

Porsche's MY98 TSB Approvals List for 996 Carrera and Carrera 4 engines Listed 241 lubricants from 109 Oil Companies or Blenders with technical details as follows;

1 - NO lubricants had a 15w cold start rating. All were rated at either 0w, 5w or 10w and most were 5w

2 - NO mineral lubricants were on the TSB

3 - The following viscosity lubricants were Approval Listed
SAE30
0w-30 - 4
5w-30 - 8

No SAE30 oils are currently Approved by Porsche (exception V6 Cayenne) due to their lower HTHS viscosity. Porsche's minimum HTHS viscosity is 3.5cSt

SAE40
0w-40 - 17
5w-40 - 108
10w-40 - 64

Generally the 10w-40 range of SAE40 viscosity lubricants was largely "semi-synthetic" and these have been superceded by 0w and 5w SAE40 lubricants.
All 10w-40 lubricants Listed by Porsche in the TSB were semi or fully synthetic

SAE50
5w-50 - 12 (Castrol 3, Eurol 1, Idemitsu 1, Meguin 1, Mobil 1, Mol 1, Motorex 1, Pentosin 1, Soprograsa 1, Tetrosyl 1)
10w-50 - 5 (Jomo 1, Kuwait petroleum 1, TotalFina 3)

Most SAE50 lubricants Listed were fully synthetic with only 1 being a semi-synthetic
Many "unknown" Brands were probably re-badged Castrol or Mobil lubricants

Since 1999 only one SAE50 oil has been Approved by Porsche and that is M1 5w-50

SAE60
10w-60 - 2 - Both are Castrol fully synthetic lubricants

No SAE60 viscosity lubricants have been Approved by Porsche since 1999. Many use this wonderful Castrol product in long distance racing. It has a history dating back to the mid 1970s and I had a hand in its development

The TSB noted above is long outdated and has been superceded at least five times since

These links may add to more understanding about engine lubricants

https://rennlist.com/forums/993-forum/342882-oil-again-mobil-1-15w-50-new-formulation.html

https://rennlist.com/forums/911-forum/341405-oil-question.html

I do not work for any Oil Company and I am retired!

Regards

1999Porsche911

Yea, Porsche is an expert in oils and seals. How often have they changed their list of appoved oils? What generation of seal are they on? When are you guys going to learn that if your car is burning a quart of oil every 600 miles or leaking from the seals, that maybe you should stop listening to Porsche and try something else.

So many of you brag about increasing the hp of your car by adding one mod or another, yet shrug your shoulders about your biggest power thief.....burning oil.

Maybe the question you should ask is ....what did Porsche change which led to the increase in leakage of seals? Is it a coincidence? I think not.


There is even an article in Total 911 magazine stating "it is well known that Mobil 1 will leak where conventional oil will not" I guess it is not as well know as the author thought...at least to some on this board.

And your question: Do you really think the german engineers @ PAG chose the gasket and sealing materials used in the M96 without understanding the effects that the synthetic oils (that they were specifying) would have on them?

Exactly!


Am I suggesting you run conventional oil in your car? Not at all. However, if you are leaking and/or burning oil, you should move away from Mobil 0W40 to a higher viscosity and use a mineral oil additive to the crankcase periodically if neccessary.

1999Porsche911

As usual, your blowing smoke again. I'll just pick out one WRONG statement you made: "Since 1999 only one SAE50 oil has been Approved by Porsche and that is M1 5w-50".

You should read the owner's manual which clearly states 15W50. The car also came factory filled with Mobil 15W50.

Sorry I caught you but I won't bother picking apart the rest of your incorrect logic. There are many intteligent people on this board and I think they can figure it out themselves.

The one about the hydraulic lifters is hillarious!! Its obvious you got your knowledge of hydraulic lifters from reading forums like this rather than hands on experience.

If you're going to attack someone, you should get your facts straight.