Zinc additive to oil?

Mark, This is my thoughts, I am sure not all will agree with me. I think this matter is blowen up way to high. If you are rebuilding a engine with a flat tappet high lift cam you would want to use a zinc additive, if you are useing a roller cam, you would not need it. I did use it when I rebuilt my DeSoto engine just for the first startup and oil change just to be on the safe side. After the engine is broken in it is not nesssary. Again this is just my thoughts.

Paul

The break-in instructions that I get with my rebuilt engines from the local machine shop require a break-in additive for the 1st 2 oil changes, and then any oil is allowed after that.

If constant use of high zddp additive was necessary, then the rebuilders and cam shops would be requiring it, and they are not.

Thanks guys. I was already thinking this was hyperbole similar to that heard when they removed lead from gas. While many predicted immediate engine failure, the more informed were reminding folks that Amoco was selling lead free gas for many years prior to the government mandated lead free gas.

Mark

After some research, I use a zinc additive and other oil and gas additives, but I do so mainly as a result of me being deeply into over-kill. I don't have nearly enough mechanical knowledge to comment as to the efficacy of these products. I'm just a worry wart.

But I have seen this subject come up on every auto site I visit, and it seems that the opinions of the cognoscenti are split roughly 50:50 on the matter, with a slight edge toward the "it's all snake oil" side.

There has been a lot of discussion regarding the removal of the zddp from motor oils and the effects that it has had on flat tappet engines.

I am not aware of ANYBODY that has ruined their used engine under normal use while using modern formulations of motor oils.

However, I am very aware of rebuilt engines that have failed in their 1st 15 minutes of run-in because of the lack of proper lubrication during the break-in of the cam and tappets. THIS is the critical time when the extra additives are necessary.

Once the mating surfaces of the cam lobes and flat tappets have been worn in, modern oil formulations provide plenty of lubrication to the cam and tappets.

Having said that, there's nothing wrong with using the additives full time, if it provides peace of mind for the owner.

I continue to fall back on the logic of the machine shops and cam rebuilders. They would not open themselves up to warranty work for failed rebuilds due to improper lubrication by lack of communication regarding full time use of oil additives if it were really necessary AFTER proper run-in.

I've had a lot of Mechanics tell me to use Shell Rotela T
in my cars,Crane Cam recommends using it when installing
a new Cam

Exactly. Rotella during break in. Optionally forever.

Maybe we should have a demo on this

I'm a believer that the flat tappet engines should have the extra zinc protection. All it takes is a bottle of STP oil treatment and you're good to go. There's more than enough zinc there, without going into the specialty high-$$$ stuff to get enough zinc. Not needed on modern engines, so I don't use any oil additives on my daily drivers.

For what it's worth, I've had three engines done at a local shop that does nothing but build racing engines. The owners wife is a friend of my wife so he agreed to do my work as a favor even though I only want standard punched overhauls. The one caveat for the warranty is that ONLY VR 1 racing oil used & the zinc IS the issue.
And the conflict continues,,,,,,,,,,,,,,,,,,,,