I've mentioned before that my 5.9 feels really weeks, like slower then my 2.4L Ricer with 100hp. It almost feels like when the transmission slips on a manuel except it's an auto. Is it possible for a auto to wear out to where it won't transfer all the power it's recieving? I planned on getting a transgo shift kit. But i don't know if that will really help with putting power down.

 

Energy is transfered from the engine to the transmission through the torque converter, I guess yours could be bad and causing that but my money is on something else.

When I toasted my converter a few monthes ago (it had 117k on it) and put a new one in I didn't feel a difference at all to tell you the truth. So I guess either mine was still working perfect until I fried it, or replacing the TC really don't help much.