I am having the same problem with my stock tires. I thought it was an alignment issue but its not.

 

same here. scalloped on the fronts/ outer edges. my bud at the garage showed me where dodge changed the allignment specs to try and prevent this from 09-10 models.

 

I bought a lifetime tire service plan from my local tire Franchise. I take the truck in every 5K for rotation and every 10K for balance. At 16K, the tires are wearing evenly and they look like they can go at least another 20k. Everything is stock on my truck.

One thing that happens with trucks is if you change the geometry a little, *** end up (Air Bags) or down (load in bed), and run the stock alignment, they may wear in unexpected patterns. A good alignment shop will adjust for it but once the tires are worn the alignment won't fix the wear.

Look for the shop where the guy uses the machine, drives the truck and then tweaks it till he feels it's right. Some gray-beards are better then the machines

 

I've got the 17" wheels with the goodyear SRA's, never been rotated or rebalanced. Fronts still look good, backs were getting bald but no unusual wear. Just replaced the back ones last week at around 38K miles.

Sounds like the 20's have some issues.