YES, IT’S A THING – VINTAGE OIL!

I am reliably informed by John Turney, a retired chemical engineer, as follows:

“The limits on ZDTP (actually the phosphorous portion of ZDTP) started with API SG oils. The use of ZDTP started about 1935. So, it [my vintage oil] is perfect for Austin engines.

“The current 20W-50 VR-1 has sufficient ZDTP because of a sort-of loophole in the specifications. Oils with a viscosity of SAE 40 and above don’t have the low phosphorus limits because catalyst-equipped cars don’t use high-viscosity oils.”

So there we have it.  Oils with an “API Service” rating earlier than SG, such as the SE and SF of my vintage oil (label on the back), don’t have the reduced phosphorus levels, so “it’s perfect for Austin engines.”

So now when some wise guy makes a crack about how the car may look all original, “But does it have original fluids?!?” I can respond with, “Funny you should ask…”