2004 Mazda 6 engine swap
2 Answers
Usually the transaxle, pedals, wiring harness's, shifter, and connectors, and maybe the ECU. Check out some Mazda forums for someone who has done the swap.
Jfro N Trina answered 4 years ago
The flywheel (and mounting bolts) from the bad engine need to go on the transplant engine. It should be resurfaced, or replaced if needed. It would be a great time to install a new clutch and pressure plate, then it should bolt right up.