The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - original motor-best oil type

John Gilbert · 06-26-2010, 12:21 PM

It doesn't matter if you run synthetic or not, but the oil has to have ZDDP in it which is a zinc additive. Zinc was eliminated recently in most oils because it shorten the life of catalytic converters.

Running without zinc will destroy the valve train in a flat tappet motor.

I run synthetic in everything I own, and pretty much wouldn't run anything else.

I know back in the late 60s, early 70s, I ran Valvoline 30wt non-detergent in my '47 216, and 49 Jimmy with a 270.

The topic of oil can get pretty controversial — just make sure you have zinc.

06-26-2010, 12:21 PM	#4
John Gilbert Registered User Join Date: Sep 2009 Location: Placentia, California Posts: 567	Re: original motor-best oil type It doesn't matter if you run synthetic or not, but the oil has to have ZDDP in it which is a zinc additive. Zinc was eliminated recently in most oils because it shorten the life of catalytic converters. Running without zinc will destroy the valve train in a flat tappet motor. I run synthetic in everything I own, and pretty much wouldn't run anything else. I know back in the late 60s, early 70s, I ran Valvoline 30wt non-detergent in my '47 216, and 49 Jimmy with a 270. The topic of oil can get pretty controversial — just make sure you have zinc.