Too old for sythentecic oil?

[kcsa75]

I had the oil changed in my 72 today. I was planning to go with Valvoline Synthetic, but the manager told me it was "too old for sythetic." I didn't push the issue as I have no issue with conventional Valvoline but afterward I got to wondering if I'm missing something. I understood that the sythentics were fine for older engines.

Any thoughts?

[AusTx68]

It was explained to me that synthetics have a lower zinc content which make then a bad choice for older non roller motors. If you decide to run synthetic it's best to add a zinc additive.

[spike38]

Originally Posted by kcsa75

I had the oil changed in my 72 today. I was planning to go with Valvoline Synthetic, but the manager told me it was "too old for sythetic." I didn't push the issue as I have no issue with conventional Valvoline but afterward I got to wondering if I'm missing something. I understood that the sythentics were fine for older engines.

Any thoughts?

There are a lot of myths about using synthetic oils in older vehicles.
Mobile 1 has a whole site dedicated to these myths. But it all boils
down to, All vehicle benefit from using synthetics, Not to say there is
anything wrong with traditional oils. Just that synthetics last longer,
And keep your engine cleaner. If you think you have a lot of sludge
in your motor, I would change it a little sooner after switching over,
The first time ( it will clean your motor). Then use recommended times.

Spike

[mrhino]

Originally Posted by spike38

There are a lot of myths about using synthetic oils in older vehicles.
Mobile 1 has a whole site dedicated to these myths. But it all boils
down to, All vehicle benefit from using synthetics, Not to say there is
anything wrong with traditional oils. Just that synthetics last longer,
And keep your engine cleaner. If you think you have a lot of sludge
in your motor, I would change it a little sooner after switching over,
The first time ( it will clean your motor). Then use recommended times.

Spike

Agreed, the only thing I would say that would not make it suitable for a older engine is: If it leaks, or burns its fair share of oil.

[LockDoc]

-
Read this thread:

http://67-72chevytrucks.com/vboard/s...d.php?t=381780

LockDoc

[Longhorn Man]

there's a few reasons not to run synthetic... but no real good reasons. (other than burning and leaking oil as mentioned)
The zink comment above holds no water, becouse there are no 'over the counter" oils on the market (including rotella) that contain enough for non roller motors.

[into69z]

Well-do you guys add a zinc additive to your fresh oil change? If you do, what do you use? I use Valvoline and I thought it had all I needed, but I wouldn't hesitate to add a zink additive if it will help. I read recently that oil is going to change in ratings soon so that it's compatible with the newer engines? any thoughts?

[OhOneWS6]

Originally Posted by Longhorn Man

there's a few reasons not to run synthetic... but no real good reasons. (other than burning and leaking oil as mentioned)
The zink comment above holds no water, becouse there are no 'over the counter" oils on the market (including rotella) that contain enough for non roller motors.

That is a matter of opinion. Valvoline VR1 still has zinc and is available over the counter. For an all out high performance engine more zinc may be desired but for a stock to mild street flat tappet motor it is plenty.

[Gene]

One very good reason for not running full synthetic oil in an older engine is that they clean your engine. Now I know that sounds crazy but when they clean an older engine it breaks loose years of metal particles and other particles that your filter cannot trap. And if your running a cellulose(paper) filter it ges even worse, I saw a study that showed that if you run an AC or FRAM or basically any non-synthetic filter you might as well not be running one at all, they cannot trap particles smaller than 20 microns. So I run Valvoline(non-synthetic) and a Mobil 1 synthetic filter.

[Longhorn Man]

Originally Posted by OhOneWS6

That is a matter of opinion. Valvoline VR1 still has zinc and is available over the counter. For an all out high performance engine more zinc may be desired but for a stock to mild street flat tappet motor it is plenty.

when I said over the counter oil, I am talking about any oil you can find at wall mart and auto zone, and places like that. Yes, you can go to NAPA and order red line synthetic or any other oil known to man kind.
I shoulda worded that properly I guess.

[treveiger]

Check this out, thats what im putting in my truck.
http://www.amsoil.com/storefront/amo.aspx

[AusTx68]

Originally Posted by treveiger

Check this out, thats what im putting in my truck.
http://www.amsoil.com/storefront/amo.aspx

A synthetic with added zinc. You can't go wrong.

I'm running a crate motor in my truck. The manufacturer clearly states DO NOT run synthetic oil unless you add a zinc additive. I would say the zinc argument does hold water.

[70cst]

http://lubriplate.com/webstore/default.aspx

This is what I use...

[Shane]

Originally Posted by OhOneWS6

That is a matter of opinion. Valvoline VR1 still has zinc and is available over the counter. For an all out high performance engine more zinc may be desired but for a stock to mild street flat tappet motor it is plenty.

the absence of ZDDP (zinc) in motor oils is irrelevant to the performance rating of an engine.

[1969stepside]

valvoline vr1 20w50 is still high zink till the end of next year

[So.Cal.Super]

Originally Posted by 1969stepside

valvoline vr1 20w50 is still high zink till the end of next year

There lowering the zinc?

Damn EPA I bet

[project 67 sub]

they better not... thats what i run grrrr

[JJorgensen52]

I ran synthetic for a bit, but my truck burns so much oil I couldn't afford it so I switched back to convetional.

As to the ZDDP (zinc) debate, I did a LOT of research into this, and what I came up with is that the current synthetic oils (Mobil1, etc) have the same level of ZDDP as the oils that it was originally in back in the early 60's. The problems with non-roller motors only developed in the late 60's when they started building factory motors with radical cams and stronger springs.

Simply put, a factory truck motor with a mild cam and non-performance springs could run on the original ZDDP levels, which are THE SAME as the current levels in synthetic oils.

Once I replace my rings and valve seals so it stops burning, my truck is getting Mobil 1. 2cents

[leddzepp]

I have used Mobil 1 for years in all of my vehicles. My 402 has always had a sticky lifter, that eventually kept tapping non-stop. I added Hyper Lube (ZDDP additive) to my crankcase and the lifter noise went away within 5 mins and has NOT returned since. Made a believer out of me, I ALWAYS use it when changing my oil now.

[70cst]

Originally Posted by 70cst

http://lubriplate.com/webstore/default.aspx

This is what I use...

GPO 15W-40

Zinc and Phosphorus Enhanced
ZDDP Formula
Ideal for High-Performance and Classic Car Engines

I forgot to list what type of oil...

[So.Cal.Super]

Ahh The great oil debate, well here are my 2 cents to add.

First let’s look at Synthetic vs. Dino oil. Synthetic oil is artificially synthesized. Think of it on a molecular level like this. You take a work bench and dump a bag of dimes out, all the dimes are the same size, even and uniformed (I’m not using a micrometer for this debate)
They transfer heat better do to this and provide uniformed lubrication.

Now let’s look at Dino oil or Conventional, Add quarters, pennies, half dollars, dollars, those gold dollars, etc. Now we have oil on a molecular level that even after refined has a whole bunch of different sizes. What this does is transfer heat less efficient and the larger molecules will clump together and allow less seepage / leaking because it provides less gaps for the smaller molecules to pass by.

How I experienced this first hand,
I changed the rear end oil in my 72 and went to a full synthetic, two days later the axel seals were leaking. I drained the oil, refilled with conventional and the leaking stopped. I was able to go almost another 2 years before they started leaking and needed to be replaced.

The saying goes if it leaks with synthetic, if will eventually leak with conventional.

So if you already have an oil burning, seeping, leaking machine. It is not recommended to switch.

As far as the Zinc debate goes.
Zinc has been drastically cut down or almost eliminated from today’s conventional oils due to catalytic converter failure. I would like to know what the conventional oil of the 60’s levels was. For this I have researched and can’t seem to find the Data any more the Hearsay.

Here are some examples of what I have found about Zinc in some of the oils out there.

Rotella T-1 Currently 700 ppm (parts per million) Per Shell it was recently reformulated,
It used to be 1200 ppm.

Castrol won’t release the information on its GTX or GTX High mileage for proprietary reasons except to say it has lower quantities of zinc. They will say their syntec 20w-50 is 1200 ppm and is recommended for flat tappet cams

Mobil 1 10w 30 has a rate of 800 ppm and this oil is used in many cars with catalytic converters with no problem.

Mobil 15-50 has 1200 ppm; this oil seems to be recommended on a lot of exotic sports cars

Valvoline VR1 Racing oil is the highest off the shelf oil I have found and at 1400 ppm it is not recommended for use in vehicles with catalytic converters.

I will add that the Lucas oil engine break in additive when mixed with 4.5 quarts (per manufacture) will give you 5000 ppm zinc.

This still doesn’t end the debate on which oil is better. Everyone will make their choice for their own reasons I just wanted to add what I have found out over the years and am sure will continue to learn as this is debated probably way past my lifetime.

[Brock]

I drive a dirt track car (olds 350 +.040). It does have a tendency to run hot (250-270). I have tried a number of diferent oils. VR1 breaks down VERY quickly 2-3 weeks is about all you can get then the oil pressure drops, Regular Royal Purple is a little better, but the best that I can find is Royal Purple XPR...does it have zinc? don't know haven't looked but I do know I changed oil in the racecar in May and I was still maintaining 50psi of oil pressure at the end of the season (Oct).

[JJorgensen52]

Originally Posted by So.Cal.Super

As far as the Zinc debate goes.
Zinc has been drastically cut down or almost eliminated from today’s conventional oils due to catalytic converter failure. I would like to know what the conventional oil of the 60’s levels was. For this I have researched and can’t seem to find the Data any more the Hearsay.

Below is some information posted on Jalopy Journal (I've shortened it slightly, posted link to the original), which was taken from Bob Olree, who was a GM Powertrain engineer. The information in the post is taken from a paper he wrote for the SAE (Society of American Engineers). It is SAE document #2004-01-2986 if you are really interested in reading it in greater depth.

Salient point, and the source of my belief that synthetics are fine, are in bold. 0.08% (800ppm) was enough to solve the wear issues that they found in high lift flat tappet cams, and non-performance engines were okay at 300ppm. Since Mobil1 is 800ppm ZDDP, I will continue to run it in all my engines.

In the end, it's just personal preference. I like synthetics because they wear better and have superior performance characteristics over a wider range of temperatures - they also don't generate sludge or break down under heat like dino oil does.

Originally Posted by http://www.jalopyjournal.com/forum/showpost.php?p=3711603&postcount=17

(Bob, who is now retired, was one of GM's Top lubrication engineers)

Engine Oil Mythology
Bob Olree
GMPT – Fuels & Lubes

All of these myths have a common theme; newer oils are bad. And this brings us to the latest myth – new “Starburst”/ API SM engine oils are bad for older cars because the amount of anti-wear additive in them has been reduced. This one has gotten big play in the antique and collector car press lately. The anti-wear additive being discussed is zinc dithiophosphate (ZDP).

Before debunking this myth we need to look at the history of ZDP usage in engine oil.

ZDP has been used for over 60 years as an additive in engine oils to provide wear protection and oxidation stability. Unfortunately, ZDP contains phosphorus, and phosphorus is a poison for automotive catalysts. For this reason ZDP levels have been reduced by about 35% over the last 10-15 years down to a maximum of 0.08% for “Starburst”/API SM oils.

Zinc dithiophosphate was first added to engine oil to control copper/lead bearing corrosion. Starting in 1942, a Chevrolet Stovebolt engine with aftermarket copper/lead insert bearing connecting rods was the standard oil test . The insert bearings were weighed before and after test for weight loss due to corrosion. The phosphorus levels of oils that passed the test were in the 0.03% range.

In the mid 1950s Oldsmobile got in a horsepower war with its Rocket engine against the Chrysler Hemi. Both companies went to high-lift camshafts and both got into camshaft scuffing and wear problems very fast. There were three solutions. Better camshaft and lifter metallurgy, phosphating the camshaft, and increasing the phosphorus level from ZDP up to the 0.08% range. Another outcome was a battery of industry wide “Sequence” oil tests. Two of theses tests were valve-train scuffing/wear tests.

Knowing that this higher level of ZDP was good for flat-tappet valve-train scuffing and wear, some oil companies dumped even more in thinking that they were offering the customer even more protection. However it was soon learned that while going above something like 0.14% phosphorus might decrease break-in scuffing, it increased longer term wear. At about 0.20% phosphorus the ZDP started attacking the grain boundaries in the iron, resulting in camshaft spalling.

Later in the 1970s, the ZDP level was pushed up to the 0.10% phosphorus range as it was a cheap and effective antioxidant, and increased antioxidancy was needed to protect the oil in Cadillacs pulling Airstream trailers from thickening to the point of not pumping. Recently, the need for this higher level of ZDP for protecting the oil from thickening has been greatly reduced with the introduction of more modern ashless antioxidants that contain no phosphorus.

Enough history, now getting back to the myth that “Starburst/API SM oils are no good for older cars. The argument put forth by the myth believers is that while these oils work perfectly well in modern gasoline engines equipped with roller camshafts, they will cause catastrophic wear in older engines equipped with flat-tappet camshafts.


The “Starburst”/API SM oil standards were developed by a group of OEM, oil additive company, and oil company experts. When developing any new engine oil standard the issue of “backward compatibility” always comes up, and indeed the group of experts spent a lot of time researching this issue. Various oil and additive companies ran “no harm” tests on older cars with the new oils. No problems were uncovered.

The new specification contains two valve-train wear tests. One is the Sequence IVA Test which tests for camshaft scuffing and wear using a 2.4L Nissan single overhead camshaft engine with slider finger followers. The wear limits were tightened from the previous oil specification which contained a phosphorus limit of 0.10%. The second is the Sequence IIIG Test which evaluates cam and lifter wear. A current production GM Powertrain 3.8L engine with the valve train replaced with a flat tappet system similar to those used in the 1980s is used. The only reason that this test engine uses this older valve train design is to insure that older engines are protected. All “Starburst”/API SM oil formulations must pass these two tests.

In addition to the protection offered by these two valvetrain wear tests and the new testing which was conducted on the formulations containing lower levels of ZDP, a review of the knowledge gained over the years in developing previous categories also indicates that no problem should be expected. The new “Starburst”/API SM oils contain about the same percentage of ZDP as the oils that solved the camshaft scuffing and wear issues back in the 1950s. They do contain less ZDP than the oils that solved the oil thickening issues in the 1960s, but that is because they now contain high levels of ashless antioxidants that were not commercially available in the 1960s.

Feb 13 2007

[So.Cal.Super]

Brock, with temps like that conventional oil will always breakdown faster. And that is some serious engine temp. Royal purples website talks about enough ZDDP to work with flat tappet or roller valve trains glad to see you are having good luck with it.

JJ Thanks for the read, I've always loved the oil Debate and that is some good reading.

Personally I will stick with my VR-1 and good filter (Napa gold or Wix) (not trying to start the filter debate) and I like using a bottle of Lucas oil stabilizer, I change it every 3k and the oil looks and smells great. And I run around at 80mph on the freeways here. Like I said we will all have our preferences and that’s what makes this always a good read.

[70cst]

I agree... Good oil info and we will all have our preferences and yet we can all learn. Great thread!!