Monthly Archives: May 2020

I think we’re all well aware that old tires pose a safety risk, not to mention the reliability issue.   Advice varies on when you should replace your tires, but it seems that most say that tires older than 7 or … Continue reading →

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] … Continue reading →

So I recently acquired two cases of some apparently vintage Valvoline oil. Labeled Valvoline Racing SAE 20W-50 Motor Oil, it looks like the same stuff that we know today as Valvoline VR-1 oil.  And as you see, this stuff is … Continue reading →