What would cause excessive wear on the outside edge of my rear tires? The wear looks like i have lots of posite camber back there, but i don't see how that is possible...
Any ideas?

 

you may just need an alignment.

No extra wear on the inside edge? If there is, it probably just needs some more air pressure.

 

excessive outside wear could mean a toe-in problem. ur tires are scrubbing instead of rolling. do as Martini sez, go for an alignment job.

 

alright, thanks guys. Yeah there is no extra wear on thse inside so it isn't a tire inflation problem, i suspected toe in. It feels kinda squirrely on the highway too, would that also be from toe in on the rears? i hope it is, then i can fix 2 problems with just an allignment

 

"squirrelly" usually indicate toe-out as the car wants to rotate. Toe-in usually is dialed in for stability but will slow the car down. but if the toe-in/out is uneven, the your car will be darty at speeds.

jack up the car and check for bushing slop....grab the wheel and shake it to see if it is pivoting left right.