Walter from Montauk, NY:
This product was recommended to me by an old-school mechanic who works on classic cars for my 68 Chevy. It aids in the proper lubrication of pistons and parts, especially on cold cranks as the additive keeps the parts lubricated with a coating. These additives were found in oils back then, but with the regulations and advances of that came later, it was eliminated from their contents.
Arthur from Millburn, NJ:
Having a couple of classic cars, I'm concerned that today's motor oils lack the zinc content required by older engines. This product eliminates that concern.
Matt from Atlanta, GA:
Bought the above to add to the oil for my 1970 Pontiac GTO. It was recommended by my mechanic. As long as my GTO is running it will have ZDDP in it.