Is it really a good idea to have Zinc mixed with synthetic oil? When I was a kid graphite was mixed with oil. My family ran it . Never a problem at 3K changes?

Valvoline VR1 oil is fully synthetic with zinc.

If you're running roller lifters, do you need zinc?

Slyfox based on what I think I know I will say yes. It still has pushrods that see a high load and a sliding type wear. Maybe not as much zinc as an old ft engine, but still some is needed.

I've been running synthetic oil in my race engines for over 3 decades and until 2017 I ran Mobil 1 10w-30. Since 2018 I've run Lucas 20W-50 and 10W-40 full synthetic until last year when we moved to Mr. Race Oil

https://mrraceoil.com/

a local oil manufacturer, running their 10W-40 synthetic oil. I've never concerned myself with how much zine is or is not in my oil nor have I added zinc to my oil, I pour it straight from the jug as formulated and I've been running roller lifters since 2000 and I have put over 1000 passes on Crower Serve Duty w/HIPPO roller lifters TWICE in my former 700+HP 468 that powered my Chevelle.

I don't think it is necessary to add Zinc to any oil, ever. If you are breaking in a new flat-tappet cam & lifters, (or even with a roller setup), I would recommend a good high-quality break-in oil such as those made by Lucas or Driven. Break-in oils already have higher levels of Zinc, so again, no need to ever add any. (Note, most break-in oils are non-synthetic which allows for proper seating of the rings).
And as 434 Olds mentioned, any of the Valvoline VR1 Race Oils, whether you choose the blue Full Synthetic that comes in black bottles, (which I use), or the standard non-synthetic dinosaur/petroleum formula in the gray/silver jug, all have high levels of Zinc in them. I believe virtually every motor oil you can buy has Zinc in it, even the Walmart house brand.

Most manufacturers ARE phasing zinc out of their oils because it harms the emission systems in modern cars, so just because you "never added zinc before and never had a problem" or always used brand X doesn't mean you wont have an issue in the future. The lack of zinc in modern oil is only supposed to be an issue on flat-tappet cams & lifters from everything I have read. If you have roller lifters, you shouldn't have an issue. Several manufacturers offer oil with zinc for older or classic cars - I use Amsoil so I buy their "Z-Rod" to use in my old Corvette with a flat-tappet 327. I've heard mixed results on zinc additives.

Here’s two oil samples of same weight in full synthetic from different companies. I’ve used both and one is much less expensive than the other.

Super Tech

Pennzoil

ZDDP in synthetic or dino oils is a good idea whether roller or not. The only time it really matters on a roller engine is IF you have a problem.

I see posts about people adding a ZDDP supplement to their oil and if you feel the need to do that then you are running the wrong oil. Very few on here are smarter about the product than the engineer designing the blend. One thing lots of guys don't realize is that too much ZDDP can turn into an abrasive. I've done lots of reading about oils and it's a really interesting topic but highly polarizing. Not quite as bad as roller lifter brands though. LOL It's polarizing because modern oils are so good that most don't have problems and will suggest only what they have used. Case in point is how many guys think Rotella is the best oil to use in a race engine.

To answer your question, yes it's a good idea to have zinc in your synthetic oil (if your application should have it) but not added as a supplement IMO.

Zinc or other extreme pressure anti-wear motor oil components come into play at the failure of the maximum film strength / load carrying capability / shear resistance value, which takes place at the same time as the boundary lubrication reaches its limit. Or just before the parts involved would seize. While that is a very necessary feature, more directly one would want to use an oil with a superior film strength rating. Along with oil flow rate and viscosity. Today's 5w30 offer the highest film strength ratings.

Like Billy said, each new revision of the API service rating has further reduced Zinc content, to protect catalytic converters and emission systems. That is why the higher-Zinc racing oils (and oil marketed for older cars, muscle cars, etc) are usually rated SL by the API, and some race oils specify they are not intended for use in street legal passenger cars. The newest API rating of SP has about half of what the old SG and SH oils had. Diesel oils historically had higher Zinc content than oils for gasoline engines, which is why (as Curtis mentioned), a lot of racers and builders used and recommended Rotella diesel oil back in the day. Many still do use it, but Diesel oils no longer have that high Zinc formula as in the past.
Markemark, thanks for sharing those links to the oil analysis. It sure looks to me like the Walmart Supertech oil is better than the Pennzoil stuff. Also, I did not know that Pennzoil manufactures Quaker State, nor that they are either owned by, or made by, Shell Oil in Houston. (I do not use any oils from any of those 3 companies, other than sometimes Rotella (Shell) in my diesel pickup). I would like to know who makes the Supertech house brand oil for Walmart.

This message has been edited. Last edited by: FootbrakeJim,

Well hell piss would be better than PENNZCRAP use VR1 3 quarts remainder 10-30 valvoline synthetic regular oil mixes fine over 15 years and no bearing problems

quote:

I would like to know who makes the Supertech house brand oil for Walmart.

"Supertech oil is made by Warren Oil Company, Inc., one of America’s largest independent lubricant manufacturers." Warren also makes Amazon Basic and the line of oil Costco carries. Tested and proven to be a very good, cost effective, product by Project Farm.

My valvoline is old oil too. High zinc not synthetic. I have been lucky never lost a flat tappet lifter or cam. Some times I think there is such a thing as too slippery,keeping the cushion of the oil off of the surface. Maybe I am wrong.

If you want synthetic oil with a good ZDDP package look at Mobil 1 racing oil. I use it in a flat tappet SBC. I have used Mobil 1 10w-30 and added Lucas zinc additive in the same motor but it seemed to settle out and turn the oil an odd color.

Eman years ago I used something called Royal Purple. Never 1 oil related failure. Do not remember why I changed. Maybe availabilty at the time.

Royal purple was all the rage probably 25 years ago with the stock, super stock, comp crowd dur to their light weight #9 and #11 IIRC but has long since fell out of favor with the company being sold and the fact that their are many racing oil companies today that offer light weight oil for the go fast crowd. If you want to use a racing oil there are many to chose from today besides Lucas and Mr. Race Oil that I mentioned I have used. MAXIMA is another that I have used. There’s also LAT, Driven, Red Line, Schaeffer and others. Most bracket racers use whatever is the cheapest and easiest to get. Again, Mobil 1 is more than good enough for most bracket racers as well cheap and easy to get.

Footbrake Jim is right, most are phasing out all of the Zinc for all street cars. I use Valvoline VR1 because it has Zinc. Looks like that MrRaceoil stuff has zinc to.
When I did my research the Valvoline VR1 seemed to be best overall in most tests and readily available so that is what I stick with now.

I have primarily used synthetic Mobil 1, Lucas & sometimes Valvoline oil; any additives (seldomly used) has been Lucas. I'll stick with proven oils that are used by a good many bracket racers & is readily available.

2BKING

Say what you will, but Amsoil has been working great for me and I see no benefit in switching. I wouldn't use Royal Purple in my weed whacker, or anything Penzoil for that matter.