Is it possible without major modifications to install the OEM dual alternator setup on a truck that came with out it? Does it mean a complee new wiring harness? The mechanical part shoudl not be aproblem just the electrical may.

Anyone done it?

 

No it isn't possible without major mods. On stock dual alternator 6.0L trucks the PCM controls the alternator selection. You will need a new PCM program or possibly the actual PCM will need to be repalced. A better option is to put a single high-output alternator on instead. I haven't used any of those (have dual alts) but I'm sure somebody will come along and recommend some good ones soon.