Need some clarity on getting flex tune for 02 silverado.

I'm wanting to get up and running with flex fuel but still unsure on what to do. With the information I have now I believe I have 2 options.


1. Install the pcm that I pulled from a salvage yard that was in a tahoe that could run flex fuel, (I believe). The only thing I could go by to know partly was the fuel tank cap, fuel rail crossover tube that is stainless steel. The pcm service # is 12200411, and the other # is 12216121. I've read that the # I'm looking for from the repository is 12216125. What's involve in figuring out if 12216121 has all the flex tables enabled? Will I have to spend credits twice this route?

2. Just flash the os 12216125 onto my truck pcm. It is an 0411 but I'm leaning towards this method won't work.

What would be the best way to get this going without spending credits twice.

Also in the mix is I'm running now a 6.0/4L80e 2bar enhanced with the stock truck pcm.

I've read about the P59 being able to 3bar but I don't plan on pushing the engine that hard right now.

My truck is a 2002 silverado.

Injectors and pump are flex capable. Just will need to redo the fuel lines.

No matter what you're spending credits twice, either for the new PCM or for the new OS you're going to write onto the PCM.

I would contact James Short at ShorTuning about a flex enabled stock OS file. I have purchased a flex enabled truck OS from him for a P59 application. He is able to add the factory flex settings into the binary through some other tools. Not sure if he can do it for a P01 though. worth a shot, try getting in contact with him.