Hey guys, working on rounding up the remaining parts needed for my 4.3 to 5.3 swap, just wanted to double check that I can put a 2000 model year wiring harness on my 2004 engine before I go and spend the money. Sources I've found seem to say it'll work fine, but thought better safe than sorry. Truck is a 2000 model as well..

Thanks all.

 

Yeah should work fine. My oil pressure sensor had a different connector but just swapped it.

 

That's the only difference I found as well (other than the throttle body, obviously).

 

Check to make sure fuel system is the same. If it's a flex fuel motor the rails will be different and the injector plugs will also be different.

 

Thanks guys, the engine is an LM4, the aluminum blocked counterpart to the LM7 so all fuel injection stuff is the same. So all I'll have to do is change the oil pressure sensor to the pre 02 one and everything else should hook right up?