What do the letters in "STP" stand for...and does it work?

Dear Car Talk

Dear Car Talk | Sep 01, 1996

Dear Tom and Ray:

For a few years I have been trying, without success, to find out just what
the letters "STP" stand for. Many calls to large, impressive lubrication
headquarters around the country revealed only that it is a "trade name" of
the Andy Granatelli Racing Team. Do you know what it means? Also, does it
work? -- Al

RAY: When I was a kid, I remember hearing that it stood for "Scientifically
Treated Petroleum." But most "large, impressive, lubrication" companies
won't take my calls either.

TOM: Does STP work? Well, the July '96 issue of Consumer Reports did a
study of motor oils using 75 New York City cabs. And their conclusion was
that STP didn't do anything to reduce engine wear. So they say it doesn't

RAY: On the other hand, we've found it to be somewhat effective as a
"repair of last resort." If someone comes in with an old heap that's just
barely running with low oil pressure -- with the oil light flickering on
and off at stoplights -- I'll often suggest they try a bottle of STP, as an
alternative to a complete engine rebuild. After all, it's eight bucks
versus 800! Why not try it, right?

TOM: And in a number of those cases, the STP actually adds enough viscosity
to bring the oil pressure back up and allows the person to keep driving the
car -- for a while.

RAY: Inevitably, between two days and six months later, the engine dies
anyway. But all the owner has lost is $8, or maybe $8 a week. And in that
time, he may have finished graduate school, joined the armed forces, or
sold the car to an unsuspecting relative.

TOM: So what does STP stand for in our garage? Short Term Panacea.

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