I am not 100% sure I have a resonator. My car is not an SRT. The non SRT exhaust is two manifold into two Cats, then two Oxygen sensors, then some down pipe and into two more Cats, then they Y together into a single pipe that goes all the way back into the final muffler in the butt of the car. I have heard people say the second set of Cats are resonators, but they look just like cats to me. Either way I will leave those to little lumps alone. Most resonators are just little straight through glass pack looking things and help to eliminate droning, if these things are cats then I still want to leave them for the state inspection guy to see them. The SRT seem to have a different set up that looks like a big muffler thing in front of the left rear muffler and the an better muffler than the non SRT in the butt. The non SRT muffler is pretty wild looking in that exhaust has to go through it twice before coming out.