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

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

#211 Post by Harlan Halsey » Wed Jun 16, 2021 5:16 am

When I acquired my first Porsche, a 1962 356 B, in 1964, Porsche had not yet convinced themselves that multi vis. oils were good enough for their cars. Drivers manuals recommend single weight oils. But all oils since the 1930s had high levels, more than 1500 ppm, of ZDDP. Engine oil has two requirements, that it circulate quickly in a cold engine on start up, and that it maintain its lubricating function when hot. The first requirement is why Porsche recommended thinner oils in colder climates and the second is why Porsche recommended thicker oils in warmer climates. I broke with Porsche and ran Quaker State 10 W 40, figuring to get improvement in both areas. 100,000 miles later my choice seemed to have been good. Since the 1970s any good quality multi vis. oil has been more than adequate. Except that about 20 years ago the oil companies removed most of the ZDDP to meet catalytic converter lifetime requirements. The loss of ZDDP was a disaster for camshafts. But the modern cars were designed around the loss of the ZDDP and they were also designed to run on very thin oil. So as a rule, the oil companies only removed the ZDDP from oils thinner than 50 W. Since the oil companies didn't announce what they were doing with ZDDP it took a while for us to find out what was happening. And we still cannot be confident because the oil companies change oil formulations without changing part numbers or announcement.
So today about the only thing which matters is whether or not the oil has at least about 1200 ppm of ZDDP in it. Brad Penn, the successor to Kendal, used to meet that standard, as do SWEPCO 306, and Mobil 1 15 W 50, and many others today. (And they all cost more pre quart than a case of Quaker State 10 W 40 did.) There is no one "best oil".
Last edited by Harlan Halsey on Thu Jun 17, 2021 3:50 am, edited 1 time in total.

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

#212 Post by David Jones » Wed Jun 16, 2021 5:50 am

You may want to edit your post. It should read in the area of 1200 ppm ZDDP not 12 ppm.
If I had known I would live this long I would have pushed the envelope a little harder.
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Harlan Halsey
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Re: What kind of oil should I use / what is the "best" oil?

#213 Post by Harlan Halsey » Thu Jun 17, 2021 3:52 am

Done, thank you David

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

#214 Post by Jim Clement » Thu Jun 17, 2021 11:11 am

I use SWEPCO 306 on advice from my engine rebuilder..
 

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

#215 Post by Ashley James » Tue Jun 22, 2021 5:03 am

The answer isa simple one if you consider the science and dismiss anecdotes.

Since the seventies fully synthetic oils have been substantially better than old fashioned mineral oils. They’re better in many ways the most obvious of which is there being thinner on start up and getting everywhere quickly and thicker in the Nevada Desert when you’d like to avoid camshaft damage, seizures etc.

The virtually eliminate wear. Think about that statement.

Mobil 1 10W60 is formulated for old or racing engines, both are more highly stressed and both need their ZDDP. There must be equivalents and they’re the best you can use if you accept science.

I think I’ve posted this before, but it’s worth repeating.

BMW tested it in the seventies, they did a million miles in a 325i and stripped it. It was still in spec.

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Synthetic v Mineral Engine Oil

#216 Post by Rene Santos » Fri Jul 23, 2021 5:48 pm

Gentlemen, I have been using SWEPCO engine oil in the 62 Super 90 and now having difficulty in the UK to find SWEPCO. I have no experience in using synthetic oil in my 356., in fact been advised against it. Use mobil 1 in my Turbo as part of the guarantee. What is the ZDDP levels in the Mobil I your using? How long have you guys been using synthetic engine oils? What are the results? Thanks
Rene Santos
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Wes Bender
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Re: Synthetic v Mineral Engine Oil

#217 Post by Wes Bender » Fri Jul 23, 2021 5:52 pm

Did you check the info here?

viewtopic.php?f=1&t=27099
Some days it's just not worth chewing through the restraints.....

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Re: Synthetic v Mineral Engine Oil

#218 Post by Doug McDonnell » Fri Jul 23, 2021 6:51 pm

I guess that you didn't like the answer that David Jones who worked in the oil industry for years gave you: viewtopic.php?f=1&t=52991&hilit=mobil+1&start=15
1965 356C 2000 BMW 740i Sport 1967 Honda CL77 There is never enough time to do it right, but always enough time to do it over.

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Re: Synthetic v Mineral Engine Oil

#219 Post by Rene Santos » Sat Jul 24, 2021 7:01 am

Hi Doug, Just read David Jones comments. Yes like it. I had a 356 S 90 cabby as a student in the 1970's as well as a 911 Carrera 2.7 and searched the farmers for their Rotella. Only ever used it in all my Porsches up until 2000. In the early days of so called 'synthetic' oils there was a reluctance to use it in older cars. My 30 years in the oil industry makes me a sceptic without evidence. Nevertheless gentlemen I much appreciate your comments.
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Thomas Sottile
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Re: Synthetic v Mineral Engine Oil

#220 Post by Thomas Sottile » Sat Jul 24, 2021 10:02 am

I have been using Amsco 20-40 for most of the last 35 years with many coast to coast trips with no apparent negative results this is in my 64 sc stock engine. O

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

#221 Post by David Jones » Sat Jul 24, 2021 12:07 pm

Tom, I assume you mean Amsoil 20-40, never heard of amsco. When I first switched to synthetic in 82 it was to Amsoil but when Mobil 1 became generally available I did my research and I switched. Nothing wrong with Amsoil it was a financial decision to do with racing costs. I had contacts in the oil industry that helped make an informed decision.
If I had known I would live this long I would have pushed the envelope a little harder.
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neilbardsley
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Re: What kind of oil should I use / what is the "best" oil?

#222 Post by neilbardsley » Wed Aug 25, 2021 7:48 am

Can I recommend

https://www.amazon.co.uk/Richard-Michel ... B00NBH1DVO

Written by a 616 engine user.

If you don't want to read the entire book skip to recommendations and common myths.

In summary use a good 10/40 synthetic like Mobil 1. I personally use a UK brand called Smith and Allen

Peter Smit
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Re: Synthetic v Mineral Engine Oil

#223 Post by Peter Smit » Tue Aug 31, 2021 1:21 pm

Rene Santos wrote:
Fri Jul 23, 2021 5:48 pm
having difficulty in the UK to find SWEPCO.
You might try https://stratson.eu/
Frank Kleijn (manager/director) told me SWEPCO has a new owner and he is now responsible for the European distribution with headquarters in The Netherlands.
There is a dealer locator on that website.
Last edited by Peter Smit on Thu Sep 02, 2021 9:29 am, edited 1 time in total.
Were are you engine #700267 ?

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

#224 Post by Mike Horton » Wed Sep 01, 2021 10:58 pm

neilbardsley wrote:
Wed Aug 25, 2021 7:48 am
Can I recommend

https://www.amazon.co.uk/Richard-Michel ... B00NBH1DVO

Written by a 616 engine user.

If you don't want to read the entire book skip to recommendations and common myths.

In summary use a good 10/40 synthetic like Mobil 1. I personally use a UK brand called Smith and Allen
+1
Mike

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

#225 Post by Mike Horton » Wed Sep 01, 2021 11:06 pm

neilbardsley wrote:
Wed Aug 25, 2021 7:48 am
Can I recommend

https://www.amazon.co.uk/Richard-Michel ... B00NBH1DVO

Written by a 616 engine user.

If you don't want to read the entire book skip to recommendations and common myths.

In summary use a good 10/40 synthetic like Mobil 1. I personally use a UK brand called Smith and Allen
+1
On Richard's book, he recently overhauled his own 912 engine, in Australia,
Mike

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