Rislone with zinc or ZDDP or STP w zinc

[60eldo]

Wondering your guys thought on these products. Which is the best one. Or is it best to use an oil with zinc already in it like Sean Pen.

[Lexi]

This has been discussed before. Probably best to buy an oil with the required zinc already added by the manufacturer. Do your research to determine what zinc levels are present in specific oil blends (intended for older engines), then proceed from there. The alternative is to mix 2 products and become one's own chemist, which may introduce problems. Just my opinion. Clay/Lexi

[TJ Hopland]

There seems to be a growing number of people that don't think adding it is as good as when its factory mix.  Seems to have to do with when its added to the mix and some of the other additives need to be left out so it stays mixed properly. Like something in typical mixes thinks the zinc isn't supposed to be there and attacks it.  For all I know those people sell pre mixed oils. 

Personally I don't do anything that special.  I consider it same as lead.  Its only a possible problem with a high revving high performance engine that gets worked hard.  Even thought some of our engines are pretty respectable performance wise they are not high revving and other than hauling around fairly heavy cars we don't tend to push them that hard.

Break in of new parts is different.  For those I would go with what ever the builder or cam company says even if it seems like normal oil with a different label and higher price. 

[Jon S]

I have been adding Red Line Break in oil (8 oz/6 quarts of conventional Pennsoil 10w/40) for years for my ZDDP requirements and engine is whisper quiet. Pre-mixed are fine but you pay a significant premium price for these products.