Mike is correct, there in no point in rebuilding a 4d55. I have a rebuilt 4d55 in my silver 1985 Mitsubishi Pickup. That rebuild cost $7800, a lot of labor and a ton of tracking down part numbers. It is a very comparable setup to this new 4d56 motor. They both have water cooled turbos, a 4d56 roller rocker head and a new 4d56 water pump. That is where the similarities end. My 4d55 has a rebuilt bottom end which is definitely not as good as a new bottom end seeing how cranks get old and wear out. My 4d55 has a rebuilt injection pump and injectors. This is a huge disadvantage as well. My 4d55 also has a smaller 50 amp alternator instead of a 75 amp found on my new 4d56.

At the end of the day it is just not worth it to rebuild a 4d55 engine. My new 4d56 makes much better power and it has new parts instead of rebuilt parts mixed with new parts. Save yourself $3500 and just buy a new 4D56 crate motor from an importer.