Someone convince me to run ZDDP

[71 super]

I too am skeptical about the zinc additive, but based on what I have read the new oils are deficient and for the few dollars extra that it costs, it is still cheaper than a cam and lifters or worse. I say do what works for you. If you have gone 60,xxx plus then I would think you are safe, but if you are rebuilding a new motor and firing for the first time $7 is cheap insurance to get to that 60,xxx point.

[prostreetC-10]

Originally Posted by DT1

I already have hard evidence. All of the cams that I have ever had must be made from some magic metal that's impervious to premature wear.

.......but doesn't that bring me right back to what's the point of the thread? You mind is made up.

Sorry about Stanford......... Can't wait for the BCS rankings on Monday!

[70cst]

I have some thoughts about this thread but I am going to count to ten and then reply ...

[Mike Bradbury]

I will explain my story then link to the rest of the debate, if you have already read it then I cannot convince you further.

When I bought my truck it had a 350 crate motor factory built and dealer installed with 14,000 mi on it. About 1000 miles before it shredded the cam I powder coated the pan. There was absolutely no signs of shavings in the bottom of the pan at the time. Reinstalled the pan and dumped in some Mobil 1 like I have run in all my newer vehicles. 1000 miles later I bent a push rod and could not figure out why, until I pulled the motor and dropped the pan. Four of the 16 lobes of the cam were in the form of shavings in the bottom of the pan with wear on the rest of the cam.
The engine had 14,000 miles on it and was plenty broken in. The valves were factory adjusted and stock springs were not applying too much pressure on the cam. The only thing different was the oil I put into the engine.

I am in process of upgrading the engine to all roller components so I will not have to worry about weather or not the zinc was or was not the problem, but I am convinced that the oil was the problem. I am at $3500 on the rebuild and upgrade, it would have been worth it to me to have spent $14 on some race oil and not had to deal with this. It could be that I have a bit of a heavy foot and like to work the engine, maybe standard driving conditions the cams hold up fine with regular off the shelf oil and the harder you drive them the more you need the zinc, because I have also heard guys say they have not had a problem, but I sure did and it is very clear that the only thing that was different in the last 1000 miles was the oil.

Here is my thread on the topic. Some are convinced some are not.
http://67-72chevytrucks.com/vboard/s...d.php?t=489474
Mike

[long69]

i'm on the fence on this too. like someone in one of the other threads on this subject said (not verbatim) if flat tappets cams required zddp we would see tons of dead ones and all the old cars would not be on the road. last time i was in da pep boise the oil additive section was mighty small and no products promoting anything for flat tappet engines, older engines, nothing to indicate that it was for this purpose- and i was looking for it specifically- although not for very long or closely. i think a good investment (already have one) is a vacuum gauge which should show a change in how well your valve train is working. which mine shows problems, but am i looking at a problem caused by not adding zddp? too early to tell? its only on one cylinder. still have to adj. the valves to make sure its not that. other than that engine runs tits. and is strong

[oldgold70c10]

I have 3 engines that are proof eough for me that, at least after break in, the ZDDP issue is a non-issue. Two of these are over 100k on the clock and still running fine.

If you can find Ticker's oil thread, someone actually posted an exerpt or a link to an article that basically says that even tough ZDDP in oil has been reduced, it is still higher than it was or equal to 1950's era levels. A friend of mine who has several classic Pontiacs which he drives quite regularly, has researched and found basically the same thing and also doesn't fret over the ZDDP levels and has had no problems.

His cars all have basically stock valve trains, and so do mine. From what I've managed to piece together, stock set-ups without high-lift cams or super-stiff valve springs seem to be pretty indiffernt to the whole ZDDP issue.

If you really want to know the recipe for disaster, take it from my truck's PO:
-Never ever change the oil
-Never ever add oil exept when you notice there is no oil pressure
-Keep driving when it starts knocking!

[JJorgensen52]

I am going to make only one post in this thread:

First, facts need to be straight. The EPA doesn't care about Zinc in oil. They care about Phosphorus, which destorys catalytic converters. Engines don't burn oil like they used to, so this really is a non-issue.

Second, ZDDP is NOT gone from oils. Take a look at the following link:
Mobil_1_Product_Guide.pdf

Not advocating Mobil 1 in specific (though I use it in all my engines, the high mileage formulation at 1100ppm zinc additives), but just to show you there is data out there and you need to do the research before you believe everything you read.

Here is the GM tech bullentin which references the 1950's ZDDP oil levels.
oil_myths.pdf
(If the link is no-worky, google "gm Techlink oil myths, it was published by a gentleman named Bob Olree, well respected GM powertrain engineer)

For people building wild motors with high spring rates and trick cams, more ZDDP is good. This is why there are racing oils. For the rest of us who have stock or mild builds, this is largely a myth.

Those are my 2 cents. Knowledge is power, use it or lose it.

[powerdriver 1958]

III. No pissing matches. Its fine to disagree, but once a thread has run its course, and degenerated into little more than an insult fest, it will be locked. While this will require a judgment call by the Administrators & Moderators.