Back when I was a teenager working part time in a Gulf oil service station the oil choice was limited, with just 2 or 3 choices. Has that ever changed with your conventional oil, synthetic oil, pure synthetic, synthetic mix, HD oil for diesels, racing oils and the list goes on.
What oil should we use in our Falcons and other older vehicles? If we have a late model engine in our cars we have many choices but with the older stock engines that isn’t the case. Zinc had been a staple item in motor oils for years until the introduction of catalytic convertors. The zinc in the burnt oil and oil vapors were clogging up the convertors. Since the federal government mandated that the convertors have a long warranty pressure was put on the oil companies to produce oil with a lower zinc content.
This is bad news for us with older cars with flat tappet camshafts which covers just about all cars before the early 80′s. The zinc in the oil cushions the load on the camshaft. Most all later cars have roller lifters which do not need the zinc.
Well what choices do we have for our Falcons? Most all conventional oils for passenger cars do not have sufficient zinc. 1,200ppm to 1400ppm of zinc per quart is recommended for the older cars and most present passenger car oils run from about 700ppm to 900ppm. There are special oils that meet the requirements such as oils used for racing, (really not legal on the road) that many major manufacturers provide, and oils from Amsoil, Wolf Head, Royal Purple and others. These are fine oils but are expensive.
I decided to try to find some readily available popular priced motor oils with elevated zinc levels. To do this I went to the Petroleum Quality Institute Of America. All of the tests are from last year so the results should be current. Just about all of the oils are HD oils for diesels but from what I read they will work well with the older engines. The weight on them is 15-40 in most cases but we usually don’t do much driving of the older cars in the winter so I don’t think the 15-40 weight would be a problem. Below is a list of some of these oils:
Citco Citgard 500 15-40 1,243 ppm
Chevron Delo 400LE 15-40- 1490 ppm
Super Tech Universal 15-40 1,239 ppm (Walmart Brand)
Kendall SAE 15-40 CJ-4 1,286ppm
NAPA 15-40 1306 ppm
Mobil Delvac 15-40 1306 ppm
Shell Rotella 15-40 1098 ppm
Motorcraft Super Duty 15-40 1098 ppm
Another option is to use your favorite conventional oil and use a zinc supplement. Many have successfully done this but you must be careful and not add too much.
It was sure easier to choose an oil when there were fewer choices.