This unforgetaable (to me) ad came up in a conversation today, IIRC,
it's from the 1970s.
Can you fill in the spaces?

You see a green mountain scene, with a  grassy slope going away from
you, and a small patch of black road at the bottom.
There is the sound of someone going up and down through the gears.
Suddenly, a red sport sedan (coupe>) comes into view on the road and
the voice -over says, "Every ________ leaving the ______  factory
rides of _____________tires". as a man exits the passenger (far) side
of the car.
"Why? Because ________________."

{Not a trick question,)