Ultimate Motor Oil Thread or Why we hate CJ4/SM oils

[hcoles]

has this happened to anyone? (sorry this is on a BMW 328 but also a generic question)

I noticed what looked like drips from the bell housing/engine block interface...



I cleaned things up real well and changed the oil - was running M1 0-40 and the oil change used the same. Now the drip seems to have stopped. I'll check again today.

I was bad and went almost 12k miles on the oil change. I wonder if the "new" oil somehow made the seal swell and reduced or stopped the leak???

Second question - BP 20-50 - I changed to BP in my 89 3.2 - How long would you go until change even if low miles? 6 months? 1 year?

[AtomicDog]

Shell has now confused me...

via email regarding Rotella T (dino) 15W-40:

Chris,

Shell Rotella T Multigrade Oils in SAE 15W-40 and 10W-30 contain approximately 1200 ppm zinc and 1100 ppm phosphorous. To put it in perspective, that's about the same amount of zinc and phosphorous found in API SJ-rated gasoline engine oils prior to 2001. Those levels have historically provided good performance in flat tappet camshaft applications.

Thank you for your interest in Shell Rotella Products!

Regards,
Edward Calcote
Staff Chemist, Shell Lubricants US Technical Information Center
http://www.rotella.com/

per telcon 10/20/08:

15W-40 has 1200 ppm ZDDP
5W-40 synthetic has 1300 ppm ZDDP.

Who has tested the "tri-blend" to get the actual #'s?

Chris

[cnavarro]

It cannot have 1100ppm P because the CJ-4 spec has a max of 1000ppm.

Blackstone tested it for me in 03/2007 and it had 946ppm of Zn, 843ppm P, and only 26ppm of boron, but thankfully, it also had lower detergency, with only 1881ppm of Ca-based detergents, which does help improve wear performance just a tad over that of a SM-rated & compliant motor oil.

The synthetic version (5w40) is still the old CI-4 formulation, which will eventually be phased out for the new spec. It's a shame that oil manufacturers didn't all do what companies like Swepco and Brad Penn did, and just come out with a new product to meet the new specs while leaving the old ones unchanged and still in production.

[WERK I]

Charles,
Have you read the latest Panorama mag? It discusses the ZDDP levels in Mobil 1 syn which leaves me totally confused on what's on the shelves out there.

[cnavarro]

You're never going to see anything anti-Mobil in Pano, that's for sure, or anywhere else Mobil is a paid advertiser, not to mention their relationship with Porsche.

Everything said in these 50 pages of this thread stand IMHO.

[jpahemi]

Charles,

Not to sound too ignorant, but are the 3.2 engines considered "flat tappet camshaft" (as mentioned in the Shell Rotella T thread)?

JP

[dshepp806]

Originally Posted by jpahemi

Charles,

Not to sound too ignorant, but are the 3.2 engines considered "flat tappet camshaft" (as mentioned in the Shell Rotella T thread)?

JP

You better believe it, bro! The flat tappett issue is whats' at hand.

Am I missing some thing here? (Of course, I'll have to READ THE ROTELLA THREAD...)

Best,

Doyle

[cnavarro]

No, they are single overhead cam (SOHC) - the Porsche 356 and 914 are flat tappet engines. Where the 911 differs from a 'modern' engine is that most new engines, like those in the 997, are dual overhead cam (DOHC), which means they use much smaller valves and more of them, allowing for lighter valves with smaller stems and much, much less valve spring pressure.

While some 911s might have less valve spring pressure than some flat tappet engines (both seat and over the nose), heads that have been rebuilt might have different install heights or aftermarket valve springs that run more pressure. A good example are those springs sold by Jerry Woods or EBS Racing that many people use on even street engines. The way they provide valve control to 8000 rpm is by having much greater spring pressure, thus requiring more Zn and P to protect the rocker pads and cams.

[AtomicDog]

Now I'm really confused. Based on this API publication

http://www.api.org/certifications/engineoil/pubs/upload/150916thAdd10308forprint-2.pdf

phosphorus content of 10W-40, 15W-40, and 20W-50 is not required to meet any stated specification for CJ-4 or SM.

Are the reduced ZDDP levels for the non-spec'd grades purely voluntary?

Chris

[CharlesJones]

My understanding is that the limit on phosphorus for the API SM specification only applies to the following grades:

0W-20, 0W-30, 5W-20, 5W-30 and 10W-30

However in the US the same additive tends to get used for all grades, and so the oil we might use (15W-40 and 15W-50, or whatever) might have the same low phosphorus levels if bought in the US. However, in Europe this isn't the case, and different grades of oils use different additive and so the heavier grades aren't effected by the low phosphorus levels.

I've also heard that if the heavier grades of oil (10W-40, 15W-40 etc) have the European ACEA A2/A3 with B2/B3 or B4 performance levels, phosphorus levels will also be at 0.10 % to 0.12%.

I got this information from:
http://www.penriteoil.com/uk/nextpage.php?navlink=Zinc%20in%20Engine%20Oils

Assuming this information is correct it would imply that in Europe at least we shouldn't have worry about low ZDDP levels. In the US I guess it would be worth checking with the manufacturer as some posters have already done, unless you have oils over there which carry the same European ACEA A2/A3 endorsement. That's my opinion anyway.

[snbush67]

Originally Posted by AshEvan

Eh Braddah, more betta you get me one case of da kine oil for my 74 911 at da base stor.

Translation:

My fellow Prosche brother in Hawaii, I would greatly appreciate if you could purchase a case of that fine oil with the proper levels of Z's and P's the next time you are at the Navy base store in Pearl Harbor.

HA! HA! HA! I am originally from Parker Ranch on the Big Island and some day will lead the ultimate 911 tour drive on the island of Hawaii starting in Kona and ending at Kilauea Volcano House for drinks and dinner.

I will gladly join you on the tour, and I will bring the oil . PM Sent

[Bart_dood]

Reading this whole thread etc is interesting but I can't help feeling this whole thing is blown a bit out of control..

Does anyone have any definitive data on old Vs modern oils regarding these additives? The testing of oils under shear conditions such as camshafts and followers is one of the most basic tests that oils undergo, I've seen it done myself at chevron.

I don't understand what is so special about the shear film requirements of a 911 engine Vs a modern engine?

[HarryD]

Originally Posted by Bart_dood

Reading this whole thread etc is interesting but I can't help feeling this whole thing is blown a bit out of control..

Does anyone have any definitive data on old Vs modern oils regarding these additives? The testing of oils under shear conditions such as camshafts and followers is one of the most basic tests that oils undergo, I've seen it done myself at chevron.

I don't understand what is so special about the shear film requirements of a 911 engine Vs a modern engine?

Confusing? Yes!

IMHO, the story goes something like this:

The issue is valid for any car with Flat tappets. In the mid-nineties, the car makers all went to roller tappets vs the older flat tappets to actuate the valves. The roller tappets do not generate as much force as a flat tappet does on the cam surfaces. Hence the roller tappets do not cause the wear the flat tappets do to the Camshafts. Rolloer tappets offer that advantage of less internal friction which translates to a small increase in power or gas mileage.

ZDDP (Zinc/Phosphorus stuff) has historicaly been used to provide wear protection to these highly stressed parts of you motor.

After this, USEPA pressed the car makers to extend the warranty on catalytic converters to 100,000 miles. The Phosphorus (the P in ZDDP) in the oil was felt to be sufficient to cause premature failure of the catalyst due to poisoning or plugging so they required the oil makers to reduce the ZDDP in the oils to protect the catalyst. Since all car makers are using roller tappets, the need for high ZDDP concentrations was not as critical so they complied without much fight.

OK?

[Bart_dood]

I still cannot see any major engineering principle difference between an upside down bucket follower (see photo) which is in essence a "flat tappet" Vs the 911 follower? I guess the bucket is free to rotate in the head where the 911 follow cannot.

There are millions of cars on the road with upside down bucket followers, some with very aggressive cam profiles and high valve spring loads for rpm's way in excess to the stock 911 engine (8-9krpm)

Once the engine is running, the follower rides on the oil film in between the cam and follower and should not be making physical contact; even if it did the low concentration of these Z & P additives could not cancel out all wear on these parts.

Two pics attached, one is the modern upside bucket style follower. The other is a modern honda VTEC cam follower setup, each cam lobe operates TWO valves and does so at RPM's way in excess of a stock 911, you'll notice the follower is the same style as the 911's.

[Bart_dood]

Not to spam with pics but here's another example of a modern engine with flat followers (tappets). This one is the air cooled 1200cc twin from BMW in their latest motorcycles, these engines do many many miles reliably with the same style tappet as our engines. They also have catalytic converters like (most) of our cars, the engine oil in them is just that, engine oil, the transmission oil is separate.

[HarryD]

Bart_dood,

The issue is maintaining a decent film on the surface of the cam and tappet surfaces. At the high pressure the flat tappets see, you need about 1200 ppm+ of P and Zn (per SAE) to allow it to last long enough to be protective.

We should also note that motorcycles do not typically use "conventional" motor oil but ones specifically formulated for motorcycles. These oils usually do have high concentrations of ZDDP.

If you go back in these posts you will note that some of the folks who rebuild engines for a living have reported that they have never seen a cat failure due to P poisoning. Therefore, I suspect that this is only a slight risk but one the car makers do not wish to bear since it can be avoided by reducing ZDDP in the oils they require to be used to maintain their warranties.

My knowledge is based on what I read here and elsewhere. Some the experts I trust (Charles Navarro, Steve Weiner) have clearly noted that older, flat tappet emgines seem to be showing wear in parts not previously seen. That, in a nutshell, is good enough for me as I have only one engine and I want it to last.

[donstevens]

Originally Posted by HarryD

After this, USEPA pressed the car makers to extend the warranty on catalytic converters to 100,000 miles. The Phosphorus (the P in ZDDP) in the oil was felt to be sufficient to cause premature failure of the catalyst due to poisoning or plugging so they required the oil makers to reduce the ZDDP in the oils to protect the catalyst. Since all car makers are using roller tappets, the need for high ZDDP concentrations was not as critical so they complied without much fight.
OK?

Don't forget, this was also an automatic excuse to allow oil blenders to save several cents per quart by lowering additive concentration. 1 cent over 100 million quarts of oil equals $1 million right to the bottom line. No wonder they complied without much fight.

I was also going to make the point that there are millions of car out there that have run High ZDDP oils for more than 25 years with neglible report of cat failure due to oil build up. In a mecahnically sound car the risk of P in the cat is almost zero.

Don

[Paulporsche]

Charles, is this significant?

Shell engineer said:

Shell Rotella T Multigrade Oils in SAE 15W-40 and 10W-30 contain approximately 1200 ppm zinc and 1100 ppm phosphorous. To put it in perspective, that's about the same amount of zinc and phosphorous found in API SJ-rated gasoline engine oils prior to 2001.

Is it possible there was an older SJ spec, prior to 2001 that had the higher levels to which he is referring?

[Bart_dood]

The Starburst Oil Myth -- The latest myth promoted by the antique and collector car press says that new Starburst/ API SM engine oils (called Starburst for the shape of the symbol on the container) (fig. 3 and 4) are bad for older engines because the amount of anti-wear additive in them has been reduced. The anti-wear additive being discussed is zinc dithiophosphate (ZDP).

Before debunking this myth, we need to look at the history of ZDP usage. For over 60 years, ZDP has been used as an additive in engine oils to provide wear protection and oxidation stability.

ZDP was first added to engine oil to control copper/lead bearing corrosion. Oils with a phosphorus level in the 0.03% range passed a corrosion test introduced in 1942.

In the mid-1950s, when the use of high-lift camshafts increased the potential for scuffing and wear, the phosphorus level contributed by ZDP was increased to the 0.08% range.

In addition, the industry developed a battery of oil tests (called sequences), two of which were valve-train scuffing and wear tests.

A higher level of ZDP was good for flat-tappet valve-train scuffing and wear, but it turned out that more was not better. Although break-in scuffing was reduced by using more phosphorus, longer-term wear increased when phosphorus rose above 0.14%. And, at about 0.20% phosphorus, the ZDP started attacking the grain boundaries in the iron, resulting in camshaft spalling.

By the 1970s, increased antioxidancy was needed to protect the oil in high-load engines, which otherwise could thicken to a point where the engine could no longer pump it. Because ZDP was an inexpensive and effective antioxidant, it was used to place the phosphorus level in the 0.10% range.

However, phosphorus is a poison for exhaust catalysts. So, ZDP levels have been reduced over the last 10-15 years. It's now down to a maximum of 0.08% for Starburst oils. This was supported by the introduction of modern ashless antioxidants that contain no phosphorus.

Enough history. Let's get back to the myth that Starburst oils are no good for older engines. The argument put forth is that while these oils work perfectly well in modern, gasoline engines equipped with roller camshafts, they will cause catastrophic wear in older engines equipped with flat-tappet camshafts.

The facts say otherwise.

Backward compatability was of great importance when the Starburst oil standards were developed by a group of experts from the OEMs, oil companies, and oil additive companies. In addition, multiple oil and additive companies ran no-harm tests on older engines with the new oils; and no problems were uncovered.

The new Starburst specification contains two valve-train wear tests. All Starburst oil formulations must pass these two tests.

- Sequence IVA tests for camshaft scuffing and wear using a single overhead camshaft engine with slider finger (not roller) followers.

- Sequence IIIG evaluates cam and lifter wear using a V6 engine with a flat-tappet system, similar to those used in the 1980s (fig. 5).

Those who hold onto the myth are ignoring the fact that the new Starburst oils contain about the same percentage of ZDP as the oils that solved the camshaft scuffing and wear issues back in the 1950s. (True, they do contain less ZDP than the oils that solved the oil thickening issues in the 1960s, but that's because they now contain high levels of ashless antioxidants not commercially available in the 1960s.)

Despite the pains taken in developing special flat-tappet camshaft wear tests that these new oils must pass and the fact that the ZDP level of these new oils is comparable to the level found necessary to protect flat-tappet camshafts in the past, there will still be those who want to believe the myth that new oils will wear out older engines.

Like other myths before it, history teaches us that it will probably take 60 or 70 years for this one to die also.

- Thanks to Bob Olree – GM Powertrain Fuels and Lubricants Group

[cnavarro]

The above post for those who are interested, is a bit out of date. It is a reader's digest version of Mr. Orlee's "How Much ZDP is Enough?", from the Powertrain and Fluid Systems Conference, presented October 2004, from when the SM and CJ-4 specifications were being discussed.

Yes, we already know there are two test sequences specifically for evaluating wear of both flat tappet and overhead cam engines for the API SM specification (as well as the CJ-4 specification for the IVA test sequence).

As mentioned somewhere in these 50 pages, the spring pressures over the nose are very different in both pushrod and overhead cam Porsche engines, significantly more than the production engines used in the aforementioned IIIG and IVA test sequences. But that is not the whole of it...

Furthermore, look at the test parameters for coolant and head temperatures.

http://www.swri.org/4org/d08/GasTests/IVAtest/default.htm

An aircooled engine operates at much higher temperatures and camshaft profiles typically have higher ramp rates, all of which contribute to the problem.

The limits for wear are rediculously high, compared to requirements set forth by the ACEA. Right from the IVA sequence:

Pass limit includes average cam wear of 120 μm maximum for API SL and ILSAC GF-3 and 90 μm maximum for API SM and ILSAC GF-4.

The IIIG sequence is a bit better, with a limit of 60 μm, and is run at higher oil temperatures and rpms to evaluate more deposits and varnish formation in engines.

http://www.swri.org/4ORG/D08/GasTests/IIIGtest/default.htm

But again, a GM 3600 V6 is no Porsche engine and quite frankly was one of the worse engines IMHO that GM ever produced.

Compared to the ACEA A3/B3 which has a cap of 15 μm for max combined and 10 μm for any single occurance.

http://www.infineum.com/information/acea2007_gasolineanddiesel.pdf

With all due respect for Mr. Olree, just as with the myth he is trying to debunk, not all engines are created equal nor can you blanket one single test to account for every engine and situation.

The definition of acceptable wear and what is considered a failure is the grey area in which we reside with performance aircooled engines. The failures (including high wear not resulting in catastrophic failure as well) are well documented with builders like Jerry Wood, Steve Weiner, and many others again aforementioned in this thread.

I give about one hour talks on the subject from time to time, but honestly, that doesn't scratch the surface.

I have and have studied every SAE publication from the 60s forward on lubricants which took me months to pour through, helping to make sense of everything, including the fact that the detergency of oil also plays a huge part in how well an oil protects and how much Zn and P is required in an oil. Then you have viscosity and the direct relationship to the HTHS viscosity and wear in both boundry, hydrodynamic, or mixed lubrication regimes. Yes, this is a very complicated subject and it's very easy to oversimplify with generalizations. There is no easy answer.