Dunlop D40 M2's

["Michael J. Funk" <mike@merc.com>]

Hello Q-listers,

My brother just got some Dunlop D40 M2's for his '93 S4.  Two questions I'm
hoping some folks can possibly help me with:

1) I was driving it over the weekend and must have run over a *large*
industrial strength bolt.  The driver rear tire went flat the next day.  I
had to get it patched...but now I lose the speed rating.  The tires were
purchased from the Tire Rack.  Any chance at getting a new tire from them or
from Dunlop directly?? He just put the tires on literally 8 days ago.
Anybody have experience with this?

2) The tires really like to wander on groove in the road.  If the road is
not perfectly even, she will definitely choose a path all by herself.  Is
the a function of the tire?  Size of tire?  or car itself?  The tires are of the
225/50 ZR16 variety.

If someone out there can share some insight, I'd really appreciate it before
I call the Tire Rack and find out what my options are.  I'd prefer not to
leave my brother stuck with a brand new (patched) tire.

Thanks,
mike