I'm looking to change the camshaft from stock to something around the Purple Shaft RT profile. Several sources says that I have to Re-Flash the ECM. My question is if a hand held such as Superchip or Jet can accomplish this? The truck has a 5.9L gas engine with stock exhaust.

 

I think you mean reset the pcm, not re flash. Those tuners cannot do that but normally pulling you're battery cables and letting the system drain any residual power will reset it

 

I also owe a GTO and when I changed the cam, I had to reprogrem the ECM due to the idle change. The idle changing is detected as a engine miss and the ECM will go to open loop to protect itself.