Motor oil info

[Mad Dog]

Due to recent EPA regulations on motor oil, the oil manufactuers have dropped the zinc content in SAE certified motor oil. Zinc burns up over time and turns to ash which leads to increased emissions. Newer model cars with OHC's and roller style cams do not have any problems with these changes. Unfortunately, older engines with flat tappet cams need the zinc to properly lube the camshaft. You see, zinc additives in oil help lube direct metal to metal contact when it occurs.

I have been hearing these stories for a little while about flat tappet cams going flat and set out to find the truth. I emailed Royal Purple, Valvoline, Quaker State, Castrol, and Penzoil. I copied the same email to Comp Cams and Crane Cams. Everybody but Penzoil replied, and they all had the same response. They all recomend using a racing grade oil with flat tappet cams. A few companies told me that it was imperative that I switch from standard oil. Even Royal Purple told me that thier sae approved synthetic oil was not enough to protect a flat tappet cam.

Racing grade oil contains more zinc than current formulations of SAE approved motor oils. This is to help metal to metal contact that occurs at high rpm and long duration high heat races. Everyone I contacted told me that these oils ensure the life span of flat tappet cams.

The high zinc content has been shown to shorten catalytic converter life, and possibly shorten the life of O2 sensors, so you get to make the choice on which you want to replace. Screw in O2 sensors are easy and relatively cheap, and catalytic converters are not that bad either. I know which ones I will take the risk on.

To date, I have not found an oil additive that will replace the zinc that is designed for prolonged use. Many break in supplements and cam break in lubes have a high zinc content, but thier manufacturers do not recomend thier use past the first part of new engine break in.

Don't take my word for it, research it yourself. I'm just here to make sure you guys have heard about the situation.

[camarojoe]

I'd be interested to see the e mail replies you got from the oil and camshaft manufacturers.

[Belair62]

It's true....I think it's most critical at break in but I would sure like to see an additive of some sort...

[copo69]

I'd like to see those emails also.

[John Brown]

Thats the same info I got from my automatic trans builder, the zink is needed to protect the bushings. He suggested a quart of straight 30W oil in the trans then finish the fill with type F.

[JRSully]

Does the subject address synthetics at all.?

[tirebird]

All the research I've read so far indicates that this is a break in problem,..not a running problem with already broken in engines. For my recent rebuild, we used Castrol 10-40 with moly lube and GM break in additive. Changed the oil at 500 miles to plain Castrol 10-40, and at 3k to Mobil 1 10-30. No cam problems and no oil burning.

My question still is if the oil marketers can't use zinc and phosphate, what are they using to reduce wear and are these substances just as good as ZDDP?