something broke in my truck today (06 5.9 auto) while driving. Had it towed and now trying to crank it over to diagnose awful noise and not have it start... which fuse do I pull?

 

The easiest way to crank the engine over without starting is to jump the starter motor with the ignition key in the off position.

On my 2004.5 truck, you can follow the primary solenoid wire (yellow in my case) to a connector just in front of the pwr mgnt module (fuse box) in front of the driver's side battery.

I just use a remote starter switch between this wire and +12V at the battery to crank the engine.

 

you could also crank it over by hand using the nut on the back of the injection pump. it will go slower so maybe you hear the noise better or maybe feel something