I ended up going with a JDM motor from LA JDM after researching quite a bit. Wanted the lowest mileage motor I could find and the price was right. Being able to look it over before buying was also something I liked about it. Took me 4 days by myself to do it, non-stop and late nights.
I swapped pretty much everything over from my USDM motor except:
- Both coolant sensors on the intake
- Lower intake
Used the lower intake because mine was rotted away on one of the water jackets, so the lower intake is the same the injectors however are not. All the sensors pretty much looked exactly the same, saved the knock sensors from the JDM and swapped the oil pressure sensor. Put a new knock sensor harness on as well. You need to swap the oil pan and strainer, the oil cooler as well along with the oil filter location. Exhaust manifolds are different so those need to be swapped. Used my fuel injector rails and timing sensors from my USDM motor. I think thats about it...
The engine I did pick was not the greatest, I used one of those borescope LED camera's off ebay to check under the valve cover, the engine I picked looked cleaner than the other one they had so thats why I picked it. On the outside it was pretty dirty though, but I just had it in my mind I was more concerned about the inside. One of the exhaust manifolds was removed and I should have checked it out, stupid me didnt. The engine ended up having a lot of carbon buildup in the intake and valves, hell one port had water in it and everything was gold color in there. I went through each port and closed the valves, sprayed throttle body cleaner in them and let them sit for a little bit to check sealing and to clean them out later with a brush. I should have done a better job of cleaning it though.
When it was all done, it started up and it runs damn good. The engine is not anywhere around 55-60k miles, probably much more. Guy there couldnt even give me a good answer when I pressed him on how they know thats the mileage either. Tried to get it smogged last week though and failed. NOx max is 512 and it was 562 at 15mph test, can be due to carbon buildup, so I seafoamed it twice and hopefully this weekend it will be good.
If I had to do it again? Probably would go with LKQ motor, more pricer though. Or even just tearing into the motor that was already in the truck. I learned, I worked, I finished. Feels good taking on a project and having an outcome I am satisfied with. I am happy with it, yes. Taking those bell housing bolts out and then the inspection plate for the torque converter bolts? Please not again...who designs these things. Anyways, learn from my mistakes, go in with a plan and inspect thoroughly if you go with a JDM motor.
Hope this helps, any questions just ask.