I have just over 40,000 miles on my truck and the rear brakes are under 20%, is that normal? I thought the rear brakes lasted alot longer...

 

Typically, you should go thru 2 to 3 pairs of front pads for every 1 pair of rear pads.
Can't say for sure about the dodges. On my 04, i replaced all 4 rotors and pads at about 30,000 miles, and never touched em again. Traded it in on an 06 with almost 80,000 miles.

 

I would have to say its nothing to worry about unless they are locking up under hard stops. Your driving habits are a big contrubiting factor as well as where you do most of your driving. City/freeway?

 

On the freeway for the most part. I have already put new pads and rotors on the front. Well I guess where is a good place to get some new rear pads and rotors? Would it be worth getting some sport rotors and pads?

 

When considering things like brakes and engine parts I like to think you get what you pay for so don`t skimp in that department. When you replaced your front rotors were they grinding? Most brake shops will try to sell you rotors weather you need them or not.
http://www.hawkperformance.com/truck/
http://www.powerslot.com/pages/slot_app_dodge.html

 

Knock off the burnouts!