Recommended Oil for a 348

I use Mobil 1 0w-40.

 

G'day Jim, I used Mobil 1 5W-50 fully synthetic engine oil in my 348. Its readily available from most auto parts shops.

I just bought two more bottles yesterday as I am gunna do another oil change.

There is no right or wrong answer here mate. Just choose an oil that rights for you. I need the thicker (50) weight because it gets quite hot out here in the outback and I need my oil pressure gauge to sit a little bit higher.

I see they had Mobil 1 0W-30 on the shelf there too. Would be nice for colder climates.
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I used Mobil 1 15/50 for 18 years in my 348.

 

You may want to check out swepco 306 15/40. Some dealers (Ferrari) use this oil. I ran this in my Porsche Turbo, great oil. S-Car Go runs this oil in there race motors, they are getting 7 to 9 races with out a major tear down. With Mobil 1, 3 races tops.

 

mobil 1 5-40w

 

+1

 

The factory recommended oil is Shell Ultra Helix or now Pennzoil Ultra Euro 5w-40 full synthetic. I may be speaking out of turn, but I think 50 weight is a bit on the heavy side for the 348 and 355. Generally a 0w-40 or 5w-40 would be preferred.

 

Ambient outside temperatures have little to do with the oil selection. I do note it can take a couple minutes longer to reach 170 degrees F before I can safely reach higher rpms that is about all. But in general, I am finding the Mobil 1 15w-50 to be a bit too thick for my liking with oil pressures higher than expected at all rpms. I intend to return to a 0w-40 or 0w-30 on my next change.

 

I use castrol syntec 10-40

am I the only one?

 

Nope...same here...been a Castrol fan for years.

 

Castrol does make a 5w-40 weight which would more closely match the factory weight.

I will be going to Castrol Syntec European Formula 0w-30 on my next oil change. It is actually almost a 40 weight if you read the data sheets for it.

 

Red Line 5w40.

 

Hugh, the factory spec on a 348 is a 10W40 weight, not a 5W40

 

I use Redline 10-40.

Ferrari dealer put in Shell 10-40 at my last service and it was foaming like a Cappucino.
Redline works great and there's no foam

 

Yes, I have heard very good things about Redline motor oil (as well as their gear oil).

 

It's not my intention to start an oil debate (there are already plenty of those on this site ) - some owners will choose a lighter weight to reduce wear and tear on the motor until it reaches operating temps, and IMO oils like redline at a 5 weight offer the same or better protection than many other oils at a heavier weight. The 348 factory spec also calls for a non-synthetic oil but I disregard that as well.

 

WAS, is the operative word...the current recommendation is a 5w-40.

And as we all know from reading Aehaas's oil articles, there is no problem with going lower on the "w" so if it originally spec'd a 10w-40, then a 5w-40 or 0w-40 is fine (in fact preferred according to Aehaas), as long as all the other specifications are met.

 

Actually it was a semi-synthetic, now Ferrari recommends a full synthetic.

 

+2

 

I was just mentioning that the factory spec is 10W40, I realize several owners prefer the 5W40.

 

This is correct, however, we find for running in SoCal, the 15-40 is fine. FWIW, I used 10-40 until Mobil 1 stopped making it for regular cars. They still have it for "high mileage" vehicles, whatever that means. I take it as having more additives than we need or want. Redline has it too, but I have decided to go cheaper in the recession.

 

I found this article interesting, its about porsche engines but I think much of it would apply to 348/55 or other Hi perf engines. Its a shop near me.




Oil
What motor oil is best for my aircooled Porsche?
(or any high performance engine)
by Charles Navarro
Last Updated 03/30/09

The purpose of proper lubrication is to provide a physical barrier (oil film) that separates moving parts reducing wear and friction, but there are many surfaces within an engine that operate with metal-to-metal contact, again popular belief, that are very highly dependant on a strong and robust anti-wear film. The top piston ring operating in sliding contact with the bore operates in a mixed lubrication regime consisting of both boundary (metal-to-metal direct contact) as well as hydrodynamic (oil film between moving surfaces) lubrication. The majority of non-corrosive wear occurs where boundary lubrication exists, especially at cam lobes, tappets, cam follower/buckets, and rockers. Oils contain dispersants, friction modifiers, viscosity modifiers, anti-foam, anti-corrosion, antioxidant and anti-wear additives, all of which can affect the strength and durability of anti-wear films. The focus of this study is on the levels of zinc and phosphorus found in motor oils and their interactions with other additives, more exactly, the zinc (Zn) and phosphorus (P) that makes up the anti-wear additive ZDDP, zinc dialkyl dithiosphosphate, as the ZDDP level is causing concern for all older engines, including aircooled Porsches, with modern oils.

What general characteristics make motor oils specifically well suited to an aircooled or other high performance engine? Aside from recommendations issued by Porsche, what makes a good oil? These oils must be thermally stable, having a very high flashpoint, low noack volatility, and must “maintain proper lubrication and protect vital engine components under the extreme pressure and the high temperature conditions” found in aircooled Porsches. Many engine builders recommend 15w40 viscosities below 90F ambient air temperatures with 20w50 for hotter climates above 90F average ambient temperatures. Porsche recommends and uses Mobil 1 0w40 as a factory fill in new vehicles and their 15w50 has been a popular choice used by many in the aftermarket in aircooled models. What was once considered a 'safe' oil is no longer as many of these lubricants have been reformulated for many reasons, not limited to allow for protection of emissions controls and for longer drain intervals.

Even prior to the introduction of the API's SM standard, there was concern that current API SL standards from back in 2003 may inhibit the backwards compatibility of motor oils, specifically referring to the limitation of ZDDP, which is "the most effective combined anti-wear and anti-oxidant additives currently available." SAE 2003-01-1957, Effect of Oil Drain Interval on Crankcase Lubricant Quality, Shell Global Solutions. The authors continue to state that oils are required to provide longer protection in severe operation but that an oils performance is "limited by environmental considerations." Furthermore, they state that it is hard to predict the effects of these reformulated oils in just a single oil change and may only be evident over an engine's lifetime. It is hard to know the full extent of the potential damage these new SM oils will have on our performance engines so chose your lubricants carefully.

Porsche’s recommendation in hand, our initial analysis from 2005 and 2006 and from virgin oil analyses going back to the 1990s, we found that then recent SH/SJ formulations of Mobil lubricants tested, including Mobil 1, have had higher Zn and P content than SL or current SM formulations. Even current "re-introduced" formulations are not the original formulations many shops and owners were used to. Aside from reduced Zn and P levels (now restored in certain products), many products with "adequate" Zn and P still use high levels of Ca detergents, well documented in various SAE publications as known for causing more wear than Ca/Mg or Ca/Mg/Na detergents, as previously used in oils like Mobil 1 15w50, back when it was API SH/SJ rated and prior to reformulation. This confirms the industry wide trend of the reduction of Zn and P from motor oils and switch to Ca-based detergents, with the eventual reduction to 0.06-0.08% or even worse, the elimination of these additives, which are essential to an aircooled Porsche engine's longevity. Depending on how detergent an oil is and which detergents are used, optimal Zn and P levels can range from 1200 to 1500 ppm, lower detergency oils requiring less Zn and P.

Many Porsche repair shops have acknowledged that these newest SM and CJ-4 motor oils are not sufficient for protecting any Porsche engine, including newer water-cooled ones. With longevity and the protection of vital engine components in mind, many shops are recommending non-approved motorcycle or racing oils, or the addition of oil supplements at every oil change, for their higher levels of protection. On newer water-cooled engines where Mobil 1 0w40 is recommended, a simple change to an oil with CJ-4 rating or preferably an oil with SL or CI-4 rating as well as a viscosity of 5w40 rather than 0w40 are two changes that can be done in addition to more frequent oil changes to ensure longevity of newer engines.

Oil companies have been cutting back on the use of Zn and P as anti-wear additives and switching to alternative zinc-free (ZF) additives and ash-less dispersants in their new low SAPS oils since Zn, P, and sulfated ash have been found to be bad for catalytic converters. One such ZF dispersant/anti-wear additive is boron, which does not foul the catalysts in the particulate emissions filters or catalytic converters. For most owners, the reduction in longevity of a catalytic converter is a small price to pay considering the many thousands of dollars it costs to properly rebuild a Porsche engine. It is worth noting that most Porsches have lived the majority of their lives with high Zn and P oils as found in API SG-SJ oils as late as 2004, and we never hear of problems with their catalytic converters.

In addition to protecting emissions controls, there are many other design considerations in formulating engine lubricants, which include improving fuel economy and longer drain intervals. Many believe that the EPA has banned zinc and phosphorus in motor oils. This is not true. In response to modern engine design and longer emission control warranties which are required by the EPA, manufacturers have turned to reformulation of oils to do this, as well as to improve fuel economy by reducing fiction. High friction can result in areas with boundary lubrication or where high viscous friction forces and drag may occur with hydrodynamic lubrication in bearings. The use of friction modifiers, such as moly (there are many different species of Mo-based friction modifiers, help to reduce friction in metal-to-metal contact with the formation of tribofilms characterized with their glassy, slippery surfaces. Lower viscosity motor oils are key to increasing fuel economy by their reduction in drag where high viscous friction occurs in hydrodynamic lubrication. While lower viscosities improve fuel economy greatly, they also reduce the hydrodynamic film strength and high temperature high shear viscosity of the motor oil, factors both of which are key to protecting high performance engines, especially aircooled ones.

However, it is worth noting that these new API guidelines do not need apply to “racing,” “severe duty,” or any motor oils that do not carry an API “starburst” seal or clearly state for off-road-use only. Motor oils meeting “Energy Conserving I or II” standards should be avoided as well as those with an API SM or ILSAC GF-4 classifications. The European ACEA A3/B3 "mid-SAPS" classifications, which place a cap on P levels at 0.10-0.12% but allow for higher Zn levels, to be better in taking into consideration wear and engine longevity, setting much lower wear limits, while still limiting emissions and protecting emissions control devices. The current ACEA A3/B3 classifications require higher high-temperature high-shear (HTHS) viscosities, stay in grade sheer stability, and tighter limits on evaporative loss (noack volatility), high temperature oxidation, and piston varnish. This makes oils meeting these ACEA standards that much better for your Porsche, especially since wear limits are much more stringent for valve train wear, 1/6th to 1/4th the wear allowed in the sequences for API's newest SM or CJ-4 standards. Of particular interest is the upcoming ACEA E9 which will incorporate some of the improvements in the CJ-4 standard along with higher Zn and P, making these mid-SAPS oils an excellent choice for older legacy engines.

Failure to use the right oil, use proper filtration, or observe proper changing intervals can affect the performance of even the best motor oil. This also includes changing the oil too often (needlessly bad for the environment and your wallet) or not often enough. Against conventional wisdom, engine wear decreases as oil ages to a certain extent, which means that changing your oil more frequently actually causes engine wear; these findings were substantiated by studies conducted by the auto manufacturers and petroleum companies, leading to standard drain intervals increased from 3,000mi/3 months to 5,000-7,500mi/6 months in most domestic vehicles, using mostly non-synthetic oils. Based off of extremely long drain intervals recommended by most European manufacturers, some in excess of two years and 20,000 mi, some users have found it best to reduce those intervals by half or even a quarter. Porsche for the 2008MY has reduced their extended drain intervals significantly to one year/12,000 mi, which is actually less miles than Porsche recommended back in the 1990s with 964 and 993 based aircooled 911s. Based on UOAs provided to us by our customers, new Porsche owners should consider reducing their drain intervals further to no more than 9,000 mi or one year and some shops recommend changes every 5,000-6,000 mi or six months (an interval we run in all our vehicles). Also, remember, Porsche drain intervals are based off a fill of min. 10 quarts, so engines with smaller sumps have to run shorter drain intervals!

Vehicles with track time or sustained high oil temperatures or RPMs should have their oil changed after every event (or every other event). This translates to a total of about 10 hours maximum combined engine operation, with vehicles with 12 qt or higher oil capacities- engines with smaller capacities must be changed more often. Vehicles subjected to very short drives or sustained operation in heavy traffic should indeed be serviced more often. Likewise, vehicles not driven often but driven hard a few times a year can probably go a year between oil changes, but that doesn't mean you shouldn't use a good oil! Regular used oil analysis is the best way to determine ideal drain intervals for your driving habits - one good rule of thumb I have seen quoted is to change the oil with the TBN (total base number) is reduced by 50% of the original total (requiring you to also know your oil's virgin TBN). Another common recommendation is to change the oil once it's TAN (total acid number) equals the TBN. Other factors to consider are fuel dilution and shearing out of grade when determining your drain interval. With this knowledge in hand, using a quality motor oil with proper filtration and regular service is the best thing to do for your engine and to protect your investment.

Any information you may receive related to this web site is provided merely as friendly suggestions, not as expert opinion, testimony or advice. Neither LN Engineering nor Charles Navarro endorses or sponsors any information, products or methodologies you may find herein. - Sorry for the legal mumbo-jumbo!

Biography for Charles Navarro

Charles Navarro is one of the founders of LN Engineering, which was started in 2002 as a manufacturer of high performance Porsche and VW components, including their Nickies line of billet aluminum nickel silicon carbide (NSC) cylinders. LN Engineering also offers custom ARP hardware, JE Pistons, and R&R Pro Connecting Rods and is partnered with Jake Raby of Aircooled Technology for their efforts in research and development. This also includes years of joint testing in the field of lubricants as well as flat tappet cams and lifters in an effort to resolve years of unexplained cam and lifter failures that coincidently started around the time the API SL standard was introduced. Rather than considering that it was a lubricant related issue, we focused on the lifters themselves and in partnership with Schubeck Racing, developed ceramic composite lifters which were excellent in eliminated cam and lifter failures and wear entirely. Not until Schubeck Racing went out of business and the supply of lifters disappeared, did we return to evaluating conventional lifters and cams. To learn more about the ceramic composite lifters we one sold, click here. Through careful evaluation of material, surface finish, and cam and lifter radius and taper was Aircooled Technology able to find an adequate solution. Not outright failure, but high wear was still a big problem using a popular 20w50. Not until we started evaluating lubricants, did we find that the oil used was just as important as all the other considerations made. For Aircooled Technology, Brad Penn was the wear solution and is required for all their engine kits and turnkey engines, right from the start. LN Engineering and Aircooled Technology have since tested many lubricants for their real-world as well as on-the-dyno performance for both wear and horsepower. Brad Penn still remains Aircooled Technology’s #1 choice in lubricant for their customers.

 

Wow, first I have heard of this!