if your dif is going out in the rear, in turns it will feel like your are puloing th ebrake, one wheel won't spin freely. i just changed my buddy's spider gear set out in his wrangler, it would lock up in tight turns when you hit the gas, both wheels spun at the same speed.

 

I don't know if its my rear diff' , but I sometimes hear a 'THUD' noise after letting out the clutch. No, its not the limited slip catching or the exhaust popping. Its metal on metal.