I tell ya, I have a pit and never thought I'd find durable toys that would last longer then a day for her. Plus they can get exspensive! Here is what i found to be "bully proof"
-Cow hoofs
-Nylabones
-Bully Sticks
-Tire Toys
-my neighbor buys wheel barrow tires for her pit but I'm nervouys about the ingestion of those
-Kongs
Pitties can chew and chew for days, I'm sure you've learned to hide your sandals, remotes, etc, haha!
Chewing is a theraputic exersice the same way a baby uses a pcifier or favorite blankie so always encourage them to chew.....the right things of course!