Engine Swap Questions - Gen3 Engine into a Gen4 Truck

[FunkedOut]

I am helping out a friend with an engine swap on a 2011 Suburban 5.3L.
The AFM caused the engine to give up the ghost.
We are swapping in a 5.3L from a 1999 Silverado.
We have the Gen3 PCM that matches that engine/truck.
There is nothing wrong with the Gen4 PCM in the 2011 Suburban.

Is there an advantage/disadvantage to keeping the Gen4 PCM?
Would we be better off swapping in the Gen3 PCM?
I don't know what I don't know and would love some input from the collective experience here.

I have experience tuning Gen3 and Gen4 GM, so that part of this is a wash for me.
My gut instinct says keep the newer Gen4 PCM, but I really have no data to back that up.

Thanks in advance for any advice/pointers/things to look out for.

[TheMechanic]

Different animals Gen 3 24X Gen 4 58X CKP pickups.
Gen 4 is generically a stronger motor but if you don't plan on a 500HP motor you will be fine with the Gen 3 as long as you have a transmission (4L80e) to match.

[FunkedOut]

This will not be anything more than a people mover.
No need for max power.

The tranny in the Suburban is a 6L80.

[gtstorey]

I don’t think you are going to be able to integrate a gen3 ECM into all of the other modules that an ‘11 will have. BCM and TCM etc

[RDF1]

You would spend more money getting all that to work together instead of just putting a Gen 4 reluctor on the gen 3 crankshaft. Then a 4x cam sprocket and you would have everything you need to run the engine with the E38 ECM.

[5FDP]

Agreed, you must swap the reluctor over and install a 4x cam gear. Then drill/tap the block for the knock sensors that the GEN 4 uses.


Or just send the GEN 4 engine out to be cleaned up, new piston rings and seals. Then install a factory sized non DoD camshaft with new non DoD lifters, valley plate etc etc. Slap it back in the truck and call it good.

[FunkedOut]

All great advice. Thank you.
Now I know what to go research in more detail.