Rislone Hy-per Lube Zinc ZDDP Supplement, Automotive Additives, 11 oz

Old cars from the 60s like my 63 Valiant need a zinc/phosphorous supplement for protection of the camshaft and valvetrain as it says on the label. Newer oils don't have this, or as much of it, so anyone who runs any old car regularly is wise to use one. Of course this car has a Slant Six and it could likely run bacon grease and still keep going. However this is some extra protection when an engine is using oils and other lubricants that were never even dreamed of back in 1963. 2nd bottle I have purchased. Will add it when I get the oil changed this March or so. I like Rislone products and just started using their Engine Treatment on an 86 Olds Calais 2.5 [136,000 miles] It seemed to make a naturally loud engine quieter and a bit smoother. It will go into every crankcase from this time forward.