Dear Tom and Ray:

I was wondering if you could answer another question about driving on the beach. I have a permit that allows me to drive on the nearby beaches, and to be able to drive
on the beach, you must first let some air out of each tire to give you better traction. The National Park Service recommends 12 psi. Of course, as you said in a previous
column, as soon as you get off the beach, you have to refill the tires to avoid tire damage on normal roads. My question is, does lowering the pressure and then filling the
tires back up affect tire balance? -- Virgil

RAY: Sure. If all the nitrogen molecules, which are lighter, ended up on one side of the tire, and all the argon molecules, which are heavier, ended up on the other, the
tire could end up seriously out of balance.

TOM: Don't listen to my brother, Virgil. He barely graduated from the Massachusetts Institute of Technology with a degree in Humanities. The answer is no. Adding or
removing air from a tire will have no effect whatsoever on wheel balance.

RAY: Unless you accidentally whack off a weight with the end of the air filler hose while you're refilling it.