Zinc in motor oils...


Compulsively Anal
Mar 23, 2008
Lee's Summit MO
As most of you already know, the Federal Government, pushed hard by the EPA, has mandated that all motor oil manufacturers remove the Zinc additive (ZDDP) from their motor oils by January of 2008. By now, almost every company has complied with this mandate.

The reason for this law is that ZDDP is damaging to the Catalytic converters in newer model cars. Since newer cars have roller cams, this change in oil should not impact engine wear.

On our cars, however (pre-87), engine wear is a BIG issue.

Without Zinc in our motor oil, our camshafts can go flat in a matter of months.

I'm planning to go with a Zinc additive with each oil change. It will cost an extra $10 per change, but worth it to me.

Here's an article that goes into more detail on this subject:

New API-compliant oils in Flat Tappat Cam Engines...

I'm just looking for everyone elses thoughts/comments on this.

There are MANY articles out there. Just do a Google search on "ZDDP oil additive".
ah, 1/2 a damn BRAIN the .gov would cancell cat ass trophic converters, put in lead tolerant O2 sensors, and put the zinc back in the oil...the only thing that ever cleaned up the air (giving a MAYBE to the Ca. guys) is electronic engine management, period....

and engines could run leaner yet, apparently, but some bogus emissions thing goes up with a leaner burn, supposedly once again.....

you all DO know it takes 10% more crude/gallon of gas for unleaded, correct??

you do know it costs about 5% of fuel economy for cat ass trophic converters, used to cost about 10% or so....

leaning out the engine electronically maybe able to get another highest of 10% in economy, but let's say 5% conversationally....

I'm sure it won't hurt anything .. $10 per oil change isn't all that bad, I assume 2 oil changes/year ??? You're getting a $5 discount when you buy the 6pack.
Yeah, by today's standards, $10 per oil change is nothing!

I know guys with diesel pickup trucks who pay $75 for an oil change!

Anyway, Zinc is such a good wear-inhibitor, that I'm definitely going to use this stuff.

I can't believe the Feds completely ignored us guys with classic cars, by removing the #1 metal-to-metal friction-reducer. Typical. Go with the tree-huggers.:bonkers:
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I've been using Royal Purple since this engine was broke-in, when we pulled the cam it looked great along with the lifters so after I broke-in the cam I went back to Royal Purple, and won't use anything else.:thumbs: