P01 6.0 to P59 5.3 Flex

Peter Tremonti · December 10, 2019

I have a 2001 Yukon XL Denali with a 6.0L with a hole in the block. I bought it this way and I was planning on swapping in a 5.3L from a 2004 Tahoe.

After looking at both of them, the 01 has an EGR valve and the 04 doesn't. The PCMs are different with the 01 being a P01 and the 04 being a P59. Is there any issue swapping from one engine and PCM combo to the other? The transmissions were both automatics but the 04 was only RWD and the Yukon is 4wd.

Either way the engine is getting being removed today and the 04 is getting shoved in there this week. I'll figure it out one way or the other. Any help would be appreciated.

I don't plan on running E85 at any point and it will be disabled in the PCM to keep it from looking for the fuel sensor as it will be missing.

CamGTP · December 10, 2019

You can't run the P59 in a P01 truck without doing a complete re-pin of the harness and likely losing some of your trucks current features.

The P01 is a red/blue harness and the P59 is a blue/green harness, or it's flipped flopped I'm just forgetting at the moment.

Install the 5.3 and tune the P01 computer to run it. It's as easy as doing a copy/paste with a yukon 5.3 tune file. (in hp tuners atleast)

You just have to keep certain 6.0 parts. Like the intake if you keep the EGR, the cable throttle body, the fuel rail/injectors.

Peter Tremonti · December 11, 2019

That's a great idea. Honestly the thought hadn't crossed my mind since the new engine doesn't have the EGR parts.

I'd like to get rid of the EGR and keep the bigger Flex injectors that came with the 5.3 if possible. Know anywhere I could find a tune for that.

I want to say the 2003 and newer have the green/blue connectors for the P59. I don't have HP Tuners but I do have TunerPro, LS Droid, and PCM Hammer to flash with.

CamGTP · December 11, 2019

You won't really find a tune for that.

You must create the tune because you have to swap so many parts of the calibration around. In the HP Tuners world I'd be copying over all the 5.3 data, then deleting the EGR function and related trouble codes. As well as finding the right flex fuel injector data and copying all that data into the correct parts of the tune. Flashing it would be the last step and making minor changes as needed based off the data logs I collect.

Peter Tremonti · December 12, 2019

Maybe the easiest thing to do is just find the stock 5.3 file for a 2001 4x4 and adjust for the 6.0L injectors? I supposed I can swap all of the EGR stuff and manifolds over for now just to keep it happy.