Pirelli Scorpion Asimmetrico's - Fast Rear Tire Wear

[rmcox1991]

Pirelli Scorpion Asimmetrico owners out there, how many miles are you getting out of your tires? I replaced all four corners in December and I've got 10K miles on them. My fronts still have 8/32" tread left but both rears are down to about 2/32". It looks like some people are getting 20K+ on their sets. I check the tire pressure regulary and I keep it at about 35 PSI. And I'm not (as my friends suggest) burning rubber at the stop lights. Kind of hard to do in an AWD 5000 lb tank! Anyone know what might be causing this? Is 10K miles normal? The treadwear rating is 420 according to Pirelli. I would think I could get more than 10K out of it. Any feedback is greatly appreciated.