strange tire wear => strut problem?

I took in my corolla for an oil change today, and the mechanic pointed out
to me that one of the rear tires was cupping (more and less worn out
segments of the tire were alternating every 5 inches or so around the whole
tire). He said, without really inspecting anything that the strut(s) need
to be replaced, and it will be around $600 if I replace all 4 of them.

Now, I'm generally suspicious of auto mechanics, especially if they speak
with barely comprehensible Arabic accent and work at a measly gas station
while driving around in an expensive looking black Mercedes.

Also, I read somewhere that if the strut covers look fine, the struts are
probably OK too.

However, that tire wear sure is irregular, and something probably needs to
be done. The problem is I don't know a single mechanic I trust. Last time I
went to a mechanic that was highly recommened by my friend's roommate, that
guy turned out to be a total dolt (I wasted time and money). I'm problably
going to rotate those tires and ignore the problem, until I can think of
something better.

>I took in my corolla for an oil change today, and the mechanic pointed out
> to me that one of the rear tires was cupping (more and less worn out
> segments of the tire were alternating every 5 inches or so around the
> whole
> tire). He said, without really inspecting anything that the strut(s) need
> to be replaced, and it will be around $600 if I replace all 4 of them.
>
> Now, I'm generally suspicious of auto mechanics, especially if they speak
> with barely comprehensible Arabic accent and work at a measly gas station
> while driving around in an expensive looking black Mercedes.


Struts could be the problem, but I doubt it. Before replacing check them on
a computer. Cupping can be also caused by worn bearings or unbalanced tires.
I would also check the alignment.

Grzegorz