91 Accord LX.

I don't know that it's the engine, I suspect it's the wheels. It is
audible at lower speeds (under 10 mph). The best way I can describe it
is a clanking noise as opposed to a grinding noise.

As far as I can tell, the car is driving fine - I get on the highway to
to to work everyday. Anti-Freeze filled, oil change done, tires changed
and balanced....

I put the question mark because I'm not even sure that the wheels are
actually the problem.