Your novel is Clifford D. Simak's "Ring Around the Sun."
From Chapter 36 of "Ring Around the Sun":
"First you shattered the economic system on which old Earth was built.
You shattered it with Forever cars and everlasting razor blades and
with synthetic carbohydrates that would feed the hungry. You destroyed
industry by producing, once and for all, things that industry could
not duplicate and things that made industry obsolete and when you
shattered industry to a certain point, war was irnpossible and half
the job was done."
Parallel Worlds of Clifford D. Simak
"Ring Around the Sun...
The hero is Jay Vickers, a writer living in upstate New York... Jay is
called to New York to meet with a man who wants him to write an exposť
of some new products that have been showing up. These are things like
a razor blade that never wears out, a light bulb that never burns out,
and, most radically, a car that will run forever: the Forever car.
George Crawford represents an industry group that is afraid of the
effect of these products on the world's economy, and he wants Jay to
write articles about the danger. But Jay distrusts Crawford and
refuses. Then his friend Horton Flanders disappears, and suddenly
people seem suspicious of Jay himself. And of anyone involved with the
Forever car and the other new products."
Ace Double Reviews, 62: Ring Around the Sun
Both hardback and paperback copies are readily available:
Amazon: Ring Around the Sun (paperback)
Amazon: Ring Around the Sun (hardcover)
My Google search strategy:
Google Web Search: simak "forever car OR cars"
I hope this is the book you're looking for! If not, please request
clarification; I'll be glad to offer further assistance before you
rate my answer.