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Vintage Castrol High Mileage synthetic blend w/quart of Lucas natural oil treatment

Just did oil change on my 122's B20. Had forgotten that in the past several mechanics recommended Castrol GTX 10w-30. Wondering what the concensus is on these older 4 cylinder engines. Another mechanic who owns a VW Vanagon (I have a 1991 Syncro van) also said he recommends regular oil in them and even uses 20w-50 in these older engines. I thought possibly a heavier synthetic might be fine.

So, I just changed the oil in my B20 with a Mann oil filter which I guess has check valve to bring up oil pressure; a quart of Lucas regular oil treatment and nearly 3 quarts of the Castrol High Mileage synthetic blend. Oil pressure seems to vascillate a little more but is still around 60; I might be wrong on whether oil pressure gauge is moving around more. Should I change the oil out back to the standard Castrol GTX? Drive only in warmer months but do live in Michigan. Also, saw that some folks like Rotella natural oil with more zinc. Any insights much appreciated!!
 
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Ah, oil. There is so much information and opinions out there, you can lose your mind.

My opinion....

Realistically, on these old engines, they are all about the same. The nice thing about true synthetics is that they are more stable than dino oil (break down less) and have no paraffin (fewer deposits). synthetics also have better corrosion protection. Generally speaking, synthetic is superior. Modern oils of all flavors don't have zinc (or very much anyway) in them. If you are worried about flattening a cam lobe, add some ZDDP additive to correct that.

That said, so what. You likely put a couple hundred miles a year on your Amazon. You will have greater problems with condensation in the crank case than any oil breakdown or other issues. As long as you change your oil annually, you should really be ok no matter what you use. 10W30 should work fine as long as you have adequate oil pressure. The only reason to switch to thicker oil in these cars is to bandaid a worn out engine.

The check valve in the oil filter helps to prevent dry starts by preventing oil from draining back into the sump. I never use filters without them.
 
nice thing about true synthetics is that they are more stable than dino oil (break down less)...

Dino oil is best for engines with blow-by...synthetics are not good..they break down.


> zinc (or very much anyway) in them

I know one brand has zinc included...
 
Dino oil is best for engines with blow-by...synthetics are not good..they break down.


> zinc (or very much anyway) in them

I know one brand has zinc included...


Source please? I'd like to read up on how synthetics break down on cars with blowby...


Most oils have zinc in them, but the levels of zinc varies greatly. The high mileage oils tend to have a little more, with M1 10w40 being around 1200ppm, while others are in the 900-1000ppm range.
 
Source please? I'd like to read up on how synthetics break down on cars with blowby...

Jan 1, 2002 - "No matter how good a synthetic oil may be when fresh, any engine oil will gradually accumulate combustion blow-by and other contaminants that cannot entirely be filtered out and thus gradually damage the oil. What's more, any synthetic oil can degrade more quickly if abused.
///
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Whether a synthetic lubricant will actually make a difference in the case of your engine all depends. How stressed are critical components on your engine such as crank bearings, rings, wrist pins, turbine bearings? How much thermal loading must your engine endure? How dangerous or expensive would it be if your engine failed catastrophically? In your case, synthetic could be overkill."
 
Hello,

Zinc and phosphorus are very important additives for the longevity of the Volvo pushrod engines.

The government mandated reduced levels of ZDDP(Zinc and phosphorus) in over the counter multi-weight engine oils to prevent premature catalytic converter failure.

However this restriction doesn't apply to 30w engine oil, a non multi-weight oil and 30w is what Volvo recommended and that is what we use.

If you want to use a multi-weight oil or synthetic, use an oil that is labeled "high in ZDDP" or Zinc like Valvoline VR1 or use a ZDDP additive.

We used to use Valvoline 30w exclusively in our customers pushrod Volvo engines, but when I couldn't get decent price breaks on cases of oil, I switched to Napa brand 30w when I found out it was made by the same manufacturer as Valvoline by a company called Ashland in Texas. I also asked my Napa parts store to verify the ZDDP content and it's adequate and we haven't had any unusual cam lobe/lifter wear while using it for the last 15 years.

FYI, about 8 years ago, we rebuilt a B20E for a customer with a 1971 1800E with fuel injection. We broke in his engine with VR1 30w and knowing that he did his own oil changes, I let him know that his preferred oil, Mobil1 5w/30w didn't have enough ZDDP and that he needed to use a ZDDP additive with all of his oil changes. And of course he didn't and just shy of 2 years later we had to change his cam and lifters. In nearly 40 years of working on engines, I have never seen such badly pitted lifters and cam lobes. 6 years later, he's still running strong and he uses his car every day for his commute to work.

Now if we would have found 1 or even 2 of the lifters that were damaged, we might have suspected other causes like a bad lifter that missed being hardened or machined improperly or bad prep on our part that caused a lifter not to spin during the engine break in procedure, but all of the lifters and camshaft lobes were badly pitted and worn. We used our regular sources for the camshaft and lifters and none of our other customers had this issue, so we think the oil was the problem as this issue has been reported by lots of others including our camshaft manufacturer.
 
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“Jan 1, 2002 - "No matter how good a synthetic oil may be when fresh, any engine oil will gradually accumulate combustion blow-by and other contaminants that cannot entirely be filtered out and thus gradually damage the oil. What's more, any synthetic oil can degrade more quickly if abused.“

A 17 year old article unsubstantiated by any data. Any oil whether synthetic or dino can degrade more quickly if abused.
 
A 17 year old article unsubstantiated by any data.

Well, Woolly Booger, or Woolly Bully...what you got to support your objection?

I would suspect Jeff has earned his stripes....and talks to industry persons, who are well learned ones. You got this under your belt?

Jeff Hartman is the author of How to Tune and Modify Engine Management Systems, Fuel Injection: Installation, Performance, Tuning, Modification, and the Turbocharging Performance Handbook, all from Motorbooks. Hartman lives in Austin, Texas.

Nitrous Oxide Performance Handbook
By Jeff Hartman
 
:rofl:

Buy a quality oil. Change it regularly. If your pressure is low (high mileage) buy a thicker oil.

Same as it has always been.

So, the quality Castrol GTX 1030 with a quart of Lucas oil treat (thick and good) used in prior oil changes over last 7 years since obtaining this beauty 122, and driven on 3 thousand mile trips several summers, will be the same as the Castrol high mileage syn blend which I just mistakenly put in?

Or, the Castrol full synthetic makes no difference as long as it is "quality" and "changed regualarly"?

What is syn oil? Is it natural mineral oil as Castrol where they alter it? Is it altogether a different beast only for modern cars with lower tolerances from machine precision assembly?

..., in my 1967 B20 that ran well on GTX

But, mineral oil breaks down too fast

Mineral oil breaks down fast when you drive it hard. Recently read that synthetic oil also dissolves the carbon deposits that seal these old engines. Would like to go to a 20w50 synthetic like Mobil 1 or other if there will be no gross issue hurting my red block.
 
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ah, oil. There is so much information and opinions out there, you can lose your mind.

My opinion....

Realistically, on these old engines, they are all about the same. The nice thing about true synthetics is that they are more stable than dino oil (break down less) and have no paraffin (fewer deposits). Synthetics also have better corrosion protection. Generally speaking, synthetic is superior. Modern oils of all flavors don't have zinc (or very much anyway) in them. If you are worried about flattening a cam lobe, add some zddp additive to correct that.

That said, so what. You likely put a couple hundred miles a year on your amazon. You will have greater problems with condensation in the crank case than any oil breakdown or other issues. As long as you change your oil annually, you should really be ok no matter what you use. 10w30 should work fine as long as you have adequate oil pressure. The only reason to switch to thicker oil in these cars is to bandaid a worn out engine.

The check valve in the oil filter helps to prevent dry starts by preventing oil from draining back into the sump. I never use filters without them.
worth repeating most of it
 
But, mineral oil breaks down too fast

Class 8 semi-truck engines are capable of one million miles between overhauls, using mineral oils...been that way for some thirty plus years.

If an older engine needs a higher level of ZDDP, then one is limited to what is available.

My experiences - Change oil/filter before OEM's stated interval, and engine will last a long time. Once a quart of oil has been lost, change oil/filter, for those engines consuming oil.

Some oils, on older engines, will be consumed quicker than other oils....find a different oil, and/or use some STP.

OEM Interval - Only good for a new engine...I do mostly highway driving, and change oil at 2k to 3k intervals on an older engine. Even with 300k miles, still running strong.

Footnote - I've maintained an Exmark riding lawn mower since new with a Kohler engine. Engine has over 1,100 hours...still runs strong....but oil (not filtered) is changed about two times during mowing season, with third oil/filter changed at end of mowing season.

Footnote - API SN PLUS, the new motor oil specification is for turbocharged engines
 
But, mineral oil breaks down too fast

I'd like to see supporting data on this topic, for the typical motorist.

IIRC, when extreme horsepower is used for extended periods (think motorsports), synthetics will do better with constant/sustained higher engine temps. For "stop-light" racers, a waste of money.

For typical NAs/Turbo engine requirements, regular oils will do just fine...especially when changed at a sooner interval than OEMs suggest.

Oil has improved greatly since Volvo suggested their requirements for redblocks. If you Google "API SN PLUS," one will find oil based upon this spec is for "a high-performance turbocharged vehicle," but not for engines needing a higher level of ZDDP
 
Drained the Castrol high mileage synthetic blend. Wow, it was rather black after only a few hundred miles, and I think it must have broke down some deposits. After reviews, and being happy with Lucas products, filled with Lucas 10w30 dino oil with added zinc. It once again sounds different, and I think I liked it better with the deposits and when I was using Castrol 10w30 dino oil with a quart of Lucas oil treatment which lasted a couple or few thousand miles between changes. It was quieter then, at least the tappets, and had a better sound. Have to build up some depositis again. Theories, but seem right.
 
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