Sign up ×  According to this answer WD-40 is not a true
lubricant. I don't get it - even Wikipedia says  The long-term
active ingredient is a non-volatile, viscous oil which remains
on the surface, providing lubrication and protection from
moisture.  which sounds quite solid.  What exactly does WD-40
lack that prevents it from being a true lubricant?
share|improve this question A side note, just because wikipedia
and\or marketing material says so, doesn't mean its true. –  Web
Jun 1 '11 at 12:57 The "WD" is short for "Water Displacement".
No citation but if I remember it was used to get water/frost off
and keep it off of space vehicles originally. –  Mark
Schultheiss Jun 1 '11 at 14:31  2 Answers 2  up vote 22 down
vote accepted  WD-40 is composed of many different chemicals,
and only about 10-20% of these are lubricants. Even then this
small amount is only a very light mineral lubricant. Most of the
other components are intended to help penetration, but are
volatile and are intended to evaporate.  WD-40 doe