On Thu, 06 Jul 2017 02:08:04 -0400, "Steve W."
wrote:

Chaya Eve wrote:
Is it normal for the outside edges of the front tires to be stairstepping
on the outer inch or two only?

By stairstepping, I mean that you can't see the wear all that much but if
you rub your hand over the tread in one direction, you can feel a lip on
each side swipe tread.

If you run your hand over in the other direction, you don't feel it. You
only feel it if you run your hand from back to front on the outside tread
of the two front tires.

If you do the same with the rear tires or on the inner edge of the front
tires, you don't feel any 'stairstepping".

The tires are about a year old and are wearing the front outside edges
only.

What you feel is known as feathering, one side of the tread block wears
more than the other. If you looked at the end of the block it would
appear as a wedge.

It is commonly caused by improper toe settings and if on one edge only
by improper camber angle as well. BUT it can also be caused by using a
common tire on a vehicle that is driven aggressively. IE high speed
cornering. That places a lot of weight on the outer edge of the tire and
tries to force it to roll under. That will wear the outer edges rapidly.

Addeing a few pounds of air pressure usually reduces the problem
significantly IF it is agressive cornrting causing the problem. We
need to know what kind of vehicle and what tires to give any more
help.

Now if you had one spot that was "normal" then a wear spot then "normal"
going all the way around the tire that would be cupping. That is
normally a suspension wear problem.