There are a few non racing type oils that still have the zinc/phosphorous additives including some diesel oils, some Amsoil synthetics too. Its my understanding that such additives may not be present in the latest standard oils because of environmental concerns and cat converter damage.
So, contary to what the article says, the latest standard may not always be best. Will have to read the article again but basically all he seems to be saying is to match the oil viscosity to the cars use.
I was wondering if I was the only one that was aware of this aswell. The article seems to imply oils with additives can be bad.
Its bad times right now for good oil for older vehicles. Our Z's grew up with oil loaded with high ppm of ZDDP in it. Recently the government keeps changing standards based on efficiency (mpg) and pollution. As noted here... the ZDDP is toxic to catalytic converters, however let me ask this.
How many people have had to replace the cat on their 83Z because it was too clogged to operate anymore?
The current laws want the catalytic converters to last the life of the car, in order to do this they came up with new standards for oil. Reduction of ZDDP for tail pipe reasons. I've been doing research on this for the last month about and still learning things; however, from what I have read is that optimal engine wear of older vehicles you should be looking at a 1200ppm-1400ppm of ZDDP in your oil. Most oils on the market are around 800ppm or lower.
Diesels are still in the loop-hole and can have higher ppm of ZDDP in their oil, but now they are a target too. The latest CJ-4 rating effectively reduced the allowable concentration of ZDDP.
So this means like stated in the quote, newer ratings don't necessarily mean better. Modern engines are built much "tighter" now days, the specs are much closer, this is why they can get away with "thinner" oils. Also engine design has improved. The rockers in valvetrains have come a long way on modern motors from our Z motor. Thus our older motors require more protection from metal on metal wear.
To compare this to medical terms for the OP... It's like having the right viscosity of blood but less oxygen in it. Yeah you will still operate but your going to encounter more problems and a shorter life span.
Great article but don't push to the side the importance of additives, detergents, and friction modifiers.