What is involved in replacing a 5.2 with a 5.9

67Dart273 said
I bet you could do nothing except change the flex plate and it would fit and run just fine. "Might be" that the TB is larger bore, don't know for sure, and computer/ injectors different.

Balancer/dampner is diff, internal vs external.

Jadaharabi said
Also Chrysler changed the rear main cap to where a 5.9 oil pan fits on the 5.2. So no problem with the oil pan.

I get different part numbers on the magnum balancer between 5.2 and 5.9. Mine looks nothing like a neutral balancer from a 5.2