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

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Bil Brown
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Re: Dino vs synthetic oil question

#166 Post by Bil Brown »

Hey you oil experts.....I`ve got a case of Castrol R bean oil left over from my 4cam daze......is there a shelf life?
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David Jones
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Re: Dino vs synthetic oil question

#167 Post by David Jones »

Just use it in the lawnmower. It will make mowing a pleasure
If I had known I would live this long I would have pushed the envelope a little harder.
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George Kehler
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Re: Dino vs synthetic oil question

#168 Post by George Kehler »

How about Joe Gibbs Driven Racing DT-50 15W50 synthetic oil. For air cooled engines !! Am putting in my 1971 911S this week. Check out their website.
George Kehler II

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Bill Lawless
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Re: Dino vs synthetic oil question

#169 Post by Bill Lawless »

Don Gale wrote: Sat Jan 18, 2020 5:46 pm
+1, My kingdom for a Pliny . . .

pliny.jpg
Nice, this is one of my favorites in VT... (Opps, how did oil discussion turn into beer discussion)
Screen Shot 2020-01-19 at 7.06.27 AM.png
Screen Shot 2020-01-19 at 7.06.27 AM.png (118.82 KiB) Viewed 6240 times
https://hillfarmstead.com/awards/hill-f ... -for-2018/
 Thanks,
Bill
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Stephen Ross
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Re: Dino vs synthetic oil question

#170 Post by Stephen Ross »

FWIW I use Rotella T4 15w40 in all my pre-1990 cars now. Good oil, cheap to buy and 1200+- ppm of ZDDP.

https://rotella.shell.com/en_us/product ... ction.html
1962 Twin Grille Roadster
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Others too

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Bill Lawless
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Re: Dino vs synthetic oil question

#171 Post by Bill Lawless »

Stephen Ross wrote: Sun Jan 19, 2020 8:40 am FWIW I use Rotella T4 15w40 in all my pre-1990 cars now. Good oil, cheap to buy and 1200+- ppm of ZDDP.

https://rotella.shell.com/en_us/product ... ction.html
Is there any advantage to running a diesel oil?
 Thanks,
Bill
65' 356 SC Cab Irish Green :D
82' SC Targa
81 VW Westfalia with 2015 Forester Engine
BMW 64'-R50/2, 75'-BMW R90/6, 74' BMW R90/6, Yamaha BW350

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

#172 Post by David Jones »

Yes, but mainly because the amount of ZDDP is not restricted as it is for the lower viscosity oils for gasoline engines. Diesel engine lubrication oils are formulated for higher operating temps and greater pressures.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
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Martin Benade
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Re: What kind of oil should I use / what is the "best" oil?

#173 Post by Martin Benade »

There is no downside to diesel levels of ZDDP?
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David Jones
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Re: What kind of oil should I use / what is the "best" oil?

#174 Post by David Jones »

Not sure what the question is Martin, but diesel oils were exempt from the restrictions on zddp levels because they were mandated for oils below 40 weight as they were considered bad for cat converters. I think the max is 800 rpm. Check the Mobil 1 chart.
If I had known I would live this long I would have pushed the envelope a little harder.
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Martin Benade
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Re: What kind of oil should I use / what is the "best" oil?

#175 Post by Martin Benade »

To rephrase, is too much ZDDP a problem for a 356, or is the 1700ish ppm OK?
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David Jones
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Re: What kind of oil should I use / what is the "best" oil?

#176 Post by David Jones »

OK Martin, now I understand. My reading and experience leads me to believe that around 2000 ppm would be getting to the point where the ZDDP could cause more problems than it solves. Too much causes the oil to tend towards an acidic concentration which is going to corrode some engine components. I doubt many of the manufacturers put that much in so the safe limit is probably around 2000 ppm. It would appear that only the motorcycle and flat out racing oils have over 1700 ppm. Personally I think I will avoid any more than a max of 1500 ppm and a minimum of 1200, then even if the formulation is off by 10% I still have a safety margin. For now I like the Mobil 1 at 1300 ppm which is a good median level. Even If I generate condensation in the engine there is not so much ZDDP that I will generate an acidic concentration.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
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Martin Benade
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Re: What kind of oil should I use / what is the "best" oil?

#177 Post by Martin Benade »

Thank you. Sounds like a more informed choice than I could make myself.
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Mike Horton
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Re: What kind of oil should I use / what is the "best" oil?

#178 Post by Mike Horton »

...if you rebuilt the VW air, fuel, and oil cooled engines, or our 616s, you as well know the differences in the modern water cooled, more thermally stable, and "way" tighter clearances, demanded to attain the somewhat unrealistic CAFE numbers required by beauracrats in DC offices with no windows.

The reality that our 616, and T4, as well as the more temp stable dry sump 911 engines, simply need higher viscosity oils, to protect the engine life, and ever increasing costly engine parts. These engines are only at nominal performance, when at "normal" operating temps.

Heed Al's, and others, when they suggest more and shorter oil change intervals, when only running the stock by-pass filters, on 616s. In my 1,000 mile since overhaul S90 engine, I added the Pre-mat full flow, and retained the by-pass filter too, for the extra qt. of capacity.

Don't go to sleep on this oil issue, as it is a moving target. Continue to do your "due diligence"...

(I've already done 2 break in oil, changes, new cast iron P/C, little iron fuzz on magnet, little consumption). I read everything David writes, but don't run synthetics.
Mike

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

#179 Post by Rick Johnston »

down to my last bottle of Pliny in the beer fridge. I wish that we could get Hill Farmstead in NC. This could be a separate thread....

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

#180 Post by Paul Lima »

My understanding is that the detergents used in modern oils (which do a pretty good job of keeping down deposits on the internals of our engines) are always in a battle with ZDDP; one wants to deposit, the other to remove deposits. Thus, getting the right balance between the two is a job for a very sophisticated chemist. My solution is to stick with an oil with a very good reputation (Swepco in my case, but there are several others)

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