ZDDP stands for zinc dialkyldithiophosphate. It was developed in the 1940’s and was a common and effective additive in engine oil.
By the 1990’s, the ZDDP level in most oil was reduced. This was due to the negative effects it has on the Catalytic Converter and
What does it do?
ZDDP helps to reduce wear and improve engine life. It also protects against corrosion and oxidation.
ZDDP is heat activated. Moving parts inside the engine create friction and heat. When this happens, the chemicals in ZDDP break down and create a “tribofilm.” This thin layer bonds to the metal surface and protects it from wear.
ZDDP is most beneficial to the camshaft and valvetrain parts. However, it is also good for the cylinder walls, piston rings, bearings, and rotating assembly.
Do I need ZDDP?
If your classic car or truck was built when ZDDP was widely used, it probably needs a ZDDP Enhanced Engine Oil. This is especially true for engines with a Flat Tappet Camshaft. If you want to use “off the shelf” oil, ZDDP Additives are also available.