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What kind of oil should I use / what is the "best" oil?

Posted: Tue Jun 21, 2011 11:08 am
by Barry Brisco
This topic is one of three new permanent "sticky" topics in the Main Discussion Forum. As long time 356Talk members know, certain topics are discussed over and over again. This is because the topics are obviously of interest to many 356 owners, and because it is not always easy to search the Forums and find earlier discussions of the topic.

Whenever a new topic is started about "what oil to use?" that topic will be locked and then linked to this permanent sticky topic, where everyone is welcome to discuss that question and share their knowledge.

In this way, those posting about a frequently asked question are quickly directed to the permanent topic about that subject, where they can find a long history of discussion and hopefully answers to their question.

NOTE: in this permanent "sticky" topic, please keep your posts focused on the subject being discussed and avoid "me too" and "I agree!" type posts that do not add useful information to the discussion. Extraneous "chit chat" type posts in this topic are subject to removal. For more information, see this topic in the Forum and Site Q&A

Thank you.

Re: What kind of oil should I use / what is the "best" oil?

Posted: Thu Jun 23, 2011 9:22 am
by Barry Brisco
Ken Daugherty wrote:I know this horse has been beaten before, but am wondering what is the latest reccomendation on motor oil for the 356. Last I heard was Shell Rotella 15-40 CJ-4 plus.
Glenn Ring wrote:I switched from Rotella T when they changed the formula to Brad Penn 10W-30.
Dave Wildrick wrote:I thought Charles Navarro said not to use CJ-4 or SM oils, but you could use Rotella CJ-4 if you added red STP or EOS.
CI Rotella 15-40 was O.K. but hard to find.
William Crowell wrote:Let's assume that you're going to change your oil about 3 times a year, based on the calendar and not mileage, and that you will be driving only about 1,000 - 2,000 miles between oil changes.

In that case, do you really think it makes a difference whether you use, for example, (a) "Super Tech"-brand oil from Walmart in whatever viscosity is your favorite (it's available in 30HD, 10W-40, 20W-50 and 10W-30, or (b) a more expensive "brand name" oil? (Let's assume you're going to use a petroleum-based oil, not a synthetic, because if you used a synthetic you probably wouldn't want to change it that often.)

The more expensive oils cost from twice to five times as much as the Walmart oil.
jay abrams wrote:As long as you run the proper weight and get the requisite ZDDP, I dont think it really matters which brand you run.
jay abrams wrote: Glenn,
Is there a way to determine the wax content by reading the label? What are some high wax content brands that should be avoided?
Brian R Adams wrote:CJ (and SM) oils have the ZDDP levels drastically reduced. CJ is specifically called out by Navarro and others to be avoided. If you are going to use a ZDDP additive, you can use pretty much any CJ/SM oild out there, nothing special in that case about Rotella.

I feel like a cuckoo clock, and find myself posting this every few weeks:

West Marine's "Premium 4-Stroke Engine Oil, SAE 15W-40" which is rated "CI-4" still has the pre-planet saver levels of ZDDP at ~$4.50 the quart.

Here is the not-so-old thread about oil:

http://porsche356registry.org/356talk/6 ... ml?start=0
Bruce Coen wrote:Brad Penn Racing Oil is getting easier to find. I bought it at my local NAPA store this spring. If you go to the Brad Penn home page, there is a "Where to Buy" link.

http://www.bradpennracing.com/Default.aspx
Joseph R Kuntze wrote:i use valvoline racing oil
high ZDDP
change every 2500 miles
full flow filter ( thanks Ron)
on sale rileys 2.99 quart 1 year
Matthew Devereux wrote:I have participated in my share of oil threads and done a bit of research and I have never heard of waxing being an issue. Perhaps this is just a thing of the past with low quality dino oils.

Re: What kind of oil should I use / what is the "best" oil?

Posted: Thu Jun 23, 2011 10:14 am
by jay abrams
Glenn,
Would you please elaborate on your waxy oil comment? How does one determine wax content? Which oil(s) have this particular issue?
Jay

Re: What kind of oil should I use / what is the "best" oil?

Posted: Thu Jun 23, 2011 11:47 am
by Jon Lieber
Hello:

I would appreciate input on whether or not it is advisable to use a partial or full synthetic motor oil in an engine that has not been rebuilt in several years. I am particularly concerned about any risk of seal failure, although I am aware that there are different opinions on this issue.

Thanks in advance for all your help.
Jon

Re: What kind of oil should I use / what is the "best" oil?

Posted: Thu Jun 23, 2011 1:16 pm
by Al Zim
Many of you will not remember how bad oil was in the 60's and earlier. I started Porsche work in 1961 and we used Kendall in the shop. The 2,000 mile oil. Now there is no reason to use synthetic oil or "racing" oil. Your 356 owners manual states that oil changes should be made at 1,500 mile intervals and at the same time lubricate the front axle. Despite what you see next to the generator on your engine this device will NEVER work as an oil filter. This is a bypass oil filter which at best will filter 5% of the oil at any given time. The only way to keep the oil clean is change it.
We used Kendall when I started foreign car work, then I had a little more college than I needed. In 1968 we started the business in my garage and have used Kendall and Brad Penn ever since. We also sell specific oils for other German cars. al zim

Re: What kind of oil should I use / what is the "best" oil?

Posted: Thu Jun 23, 2011 1:47 pm
by Mike Horton
I have been using Shell Rotella T 15 W 40 petroleum oil in my '68 912, with a well used 69,000 mile original engine since I got it back on the road after 23 years storage, 11,000 miles ago. With a preventative/defensive/protective overhaul pending, I called Shell's tech line 3 weeks ago, and asked about the ZDDP content, and was assured that it does still have over 1200 ppm of the needed ZDDP additive. The owner's manual in my old '60 T5 , page 52 says:

"IMPORTANT!
For engines of the type 1600 Super good quality HD-oil for Diesel engines should be used....
If the 1600 engine is used for competition driving, good quality HD-oil for diesel engines should be used."

After successfully using the Aero Shell aviation oils in my 50 year aircraft maintenance career, to include running an air cooled aircraft piston engine overhaul shop, I decided to trust the Shell folks with my treasured type 616 original. As I had horrible luck with the full synthetics in aircraft engines when it first came out, and the low use most of our cars see, I will stay with this less costly petroleum based oil, build up with MOS2 assembly lube, and keep the engine cleaner, through more frequent oil changes, a concept proven in my old shop, and backed up with decades of oil analysis. I did, however want to confirm the ZDDP content, as this was a serious issue in aviation piston engines about 20 years ago, causing much valve train wear. The Brad Penn, Valvoline Racing, and others will serve as well, just do some homework, and reading, stay abreast of this important issue, so you will not have to hear, "i told you so..." Fortunately for us, we still have choices. Out here in Texas (triple digit temps for the last two weeks and more to come), the Shell Rotella T, Chevron Delo, and other oils for the diesels are readily available at every parts store, Sam's Club, etc. due to all the cowboy's diesel pick ups. I have owned these 356 cars since '64, and have never gone wrong following the advice of those old factory German engineers. I am as impressed with the German engineering, as with the cars they produced... and Al's experience, like others who've "been there"... (and yes, I realize oils & engineering have advanced since the '60s)
just my $.002
Mike (TX)

Re: What kind of oil should I use / what is the "best" oil?

Posted: Thu Jun 23, 2011 6:18 pm
by Al Zim
Mike: I am probably one of the few individuals that realize when you are in Lubbock Texas that you may have to drive a long way to get a meal of see civilization. I am not going to take issue with you about what brand of oil is best. The ZDDP is most beneficial when the engine is being broken or under heavy load. Not many people will encounter the 85 MPH speed limit on I 20 that takes you to El Paso and puts the engine under heavy load. The car is comfortable in the 60 to 70 MPH bracket and thus is not a heavy load. So ZDDP is good but not critical. The point of my post was that the oil should be changed every 1500 miles since there is no other way of eliminating the dirt that gets in the oil. You did neglect to mention how often you change the oil in your car.
This would be critical in West Texas where blowing dust is a real situation. al zim

Re: What kind of oil should I use / what is the "best" oil?

Posted: Fri Jun 24, 2011 12:42 am
by Mike Horton
Al, my old friend, I was, in fact, agreeing with you, and yes, few realize how far out in West TX we are. And, yes, in this dry, very far above average dust year, like in my aircraft experience, air filter maintenance is as important to long engine life, as is the oil maintenance. Neglect in this air filter area shows up in the oil analysis as "silicone", which is very hard on the engine's internals. Though I've used them, I am not a fan of the wire mesh air filters. I'd use the Brad Penn, the old Kendall oil, as it has proven itself in service, as the Aeroshell oil did for us in aviation. Often, the remote location out here dictates what we have available. Now for some numbers. Yes, my 5 speed 912, used the most in my 375 mile/week commute to Amarillo, when I worked at Bell up there, cruises at interstate speeds of 69 mph at 4:00 in the mornings, and runs cool. The return trip back south on Friday afternoons, yielded 74 mph and not as cool, or one wasted a lot of time with Constables or Sheriffs. They work those interstates like a slot machine up here. In aviation, we used a 50 hour oil and filter change interval for engines equipped with full flow oil filters, and this regimin gave full engine life, but to go further, shortened the engines life, especially if turbocharged. I suggested a 35 hour change interval for those engines. For the earlier engines NOT equipped with full flow filtration, but with metal screens, we used a 25 hour change interval. With your 60 mph average speed, 25 hours yields the 1500 mile oil change interval... let's see, I wonder where those German Engineers got the 1500 mile figure. I will always yield to you and other long time Porsche shop owners, as you see more of these cars in a month, than most of us will in a lifetime. My decades of aircraft experience sure does parallel with a lot you post here, and thanks for taking the time. The one thing we both are in concert on, is the use of synthetics. Most folks, when they pay the premium for these "boutique" oils, want to run them longer, to justify the cost. I am of the school of thought that an air cooled engine is only partially described as "air cooled". The oil, is also the cleaning, and a cooling medium, as well, so to properly keep the engine clean internally, I'll continue to use the less costly petroleum based oils (no inferior brands here, they are out there), change more often, and follow what 50 years of aircraft engine experience taught me is successful... an ongoing preventive maintenance plan. 1500 to a max of 2000 miles has always worked for me. When a machine sees less use, change more often. And allow for anomalies like the "dusty" times of the year. Oil is one of the cheapest things we put in a car. If you don't believe me, put a teenager in one...
Mike (Cotton will be up in price this year, as only the irrigated guys will survive this drought... and other parts of the country are under water)

Remember, I saw you & Ed tow the old race speedster away from Lubbock, so many years ago...

Re: What kind of oil should I use / what is the "best" oil?

Posted: Fri Jun 24, 2011 12:29 pm
by Larry Coreth
BTW, the B/C shop manual shows 3000 mile intervals for oil change except for city driving in cold weather, where 1500 mile is recommended .

Re: What kind of oil should I use / what is the "best" oil?

Posted: Fri Jun 24, 2011 2:36 pm
by Brian R Adams
Mike,

I believe it that someone on the phone told you ZDDP level was as high as ever in the Rotella oil, but if it is of recent vintage and rated CJ /SM, than I'll wager a small sum it has ZDDP levels well below 1200. The popular diesel oils' formulations were changed to meet the strict emissions rules that went into effect for model year 2007 on-road trucks. The new additive restrictions forced formulators to reduce, if not eliminate, the use of ZDDP.

If you can find a diesel oil like Rotella or Chevron Delo still rated CI-4 or CI-4 Plus (or SL), you are a more astute shopper than I am. I don't think the old formulations are available from Shell and Chevron.

Whether ZDDP really matters (as discussed by Al Zim) is another matter entirely. But if you believe ZDDP matters, then I would consider a more rigorous approach to determining what's in the oil.

Re: What kind of oil should I use / what is the "best" oil?

Posted: Thu Aug 04, 2011 11:18 am
by Salvatore Inciardi
My suggestion is to look at other experts in other areas of vintage car collecting...

A suggestion: look at info from the National Corvette Restorer's Society...I post a link for your use....

http://www.ncrs.org/forums/showthread.p ... l&uid=8513

My take away is, if the first API designation is a "C" it is a high zinc content oil and that has not changed, regardless of brand...See the oil analysis report included in the thread.

Re: What kind of oil should I use / what is the "best" oil?

Posted: Thu Aug 04, 2011 12:13 pm
by Matthew Devereux
Brian R Adams wrote:Mike,

I believe it that someone on the phone told you ZDDP level was as high as ever in the Rotella oil, but if it is of recent vintage and rated CJ /SM, than I'll wager a small sum it has ZDDP levels well below 1200. ...
The 1200 number is what I base my selection on (per Charles Navarro). Unless the manufacturer provides published chemistry data sheets showing Zn and P levels above 1200 ppm I would not use the oil. This is easier to find with 20W50 oils than with lower viscosity oils.

Re: What kind of oil should I use / what is the "best" oil?

Posted: Thu Aug 04, 2011 7:26 pm
by Brian R Adams
Salvatore, I found the Corvette forum useless, difficult to navigate (threading is poor) and far less informative about ZDDP than this forum.

I repeat (again): Any oil rated "CJ" has levels of ZDDP far, far below 1200 PPM, and were formulated for low-sulfur diesel fuels and newer low-emissions diesel engines (you know, the ones that chucked the previously outstanding fuel efficiency of diesel engines in order to save the baby polar bears?)

You simply cannot buy good old Rotella or Chevron Delo 400 oil and get the old ZDDP levels. If anyone can point us to Rotella rated "CI-4" or "CI-4 Plus" (but not "CJ-4") please do!

Re: What kind of oil should I use / what is the "best" oil?

Posted: Thu Aug 04, 2011 8:04 pm
by Salvatore Inciardi
http://www.westcoastwillys.com/WCW_Sept08_small.pdf
SEE Page 3


http://www.shell.com/home/content/rotel ... s/tpl_pro/
Both the 15W-40 and the 10W-30 formulations still carry API CI-4 and CJ-4 designations. Nothing has changed as far as I can tell.

You can get this today on the shelves in any store that carries Shell Rotella T...if you can't find it, go to your local Walmart and then go to the automotive section....

Chevron also offers Delo LE CJ-4 in a 10W-30 viscosity grade as well as 15W-40. Here's the link
http://www.dooilco.com/pdf/Motor%20Oils ... 15w-40.pdf

I did find one interesting document from Mobil. While I know many are not fond of synthetic oils, and that's a personal choice, I did find a current document listing the zinc and phosphorus content in Mobil 1 oils. They were surprisingly high.
Here's the link
http://www.mobiloil.com/USA-English/Mot ... _Guide.pdf

So much for the sky falling!

Brian, what is your research basis for the position you are taking?

PS.....All of this information was in the NCRS Tech Forum.

Re: What kind of oil should I use / what is the "best" oil?

Posted: Fri Aug 05, 2011 2:19 am
by Brian R Adams
Salvatore,

When an oil bottle says "CJ-4, CI-4" it means it meets the newer and more stringent "CJ-4" which requires the reduced ZDDP and trumps the "CI-4" part. Just because it also meets the older CI-4 requirements doesn't mean it also has the levels of ZDDP that were present in CI-4 or CI-4 Plus formula. I know it's confusing, so I should have said if you see "CJ-4" (and/or "SM") on the bottle, stop right there, read no further, and forget it, it is not what you are looking for (if you are looking for the old high levels of ZDDP.)

Simple, huh?

I cite Charles Navarro's (a sometime contributor to this forum) treatise on this topic. Some excerpts (added italics for emphasis are mine):

"I do not recommend the use of any SM or CJ-4 motor oils in any air-cooled Porsche"

"Many cam manufacturers have recommended Rotella T in the past for cam break in. Remember, this was the CI-4 Rotella T some manufacturers were recommending, not the new CJ-4 Rotella."

Here are typical P (Phosphorous) and Zn (zinc) for the older and newer API ratings:

CI-4: P:1150 Zn:1374
SL: P:994 Zn:1182
CJ-4: P:819 Zn:1014
SM: P:770 Zn:939

Read Charles' entire treatise here:

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