Truck Repair: M11 shutting off randomly, safety standpoint, wire weather

Question
Cliff,
I have a 94 Intl 9200 w/M11. Almost every day, at least one time during the day my engine will just shut off. No coughing, or sputtering, it's like you turned the key off. Most the time it happens when I'm driving. I suspect it is a wire or short somewhere, since I usually open the hood, jiggle or move wires all around the engine and it will start back up. Other than this it runs great. This problem began after I had a dump bed put on it, but just can't see how that would affect it. There are no warning lights illuminated on the dash.  

Where is a good place to start to figure this out? I'm concerned from a safety standpoint.
Thanks

Answer
Good ole Navistar just want listen to what we recommend on the unswitched battery wiring.IHC runs the unswitched battery wires for the ECM from the starter instead of running the to the battery like every other OEM like Cummins recommends.Alot of IHC trucks log a 434(low battery voltage)when they are first started up.Have to cut engine off for 5 secs & restart it to get eng light off.I would disconnect the neg battery cables & remove the unswitched wiring harness & check for the positive(2 purple ones) for rubbing the ECM or block.Also check the wire to the fuel pump solenoid.Have seen that small wire break at the terminal & the insulation holds it together.The unswitched battery harness is real short(6 in,(starter to engine harness).It has a 3 wire weather-pak connector.The 2 pos wires are in one eyelet on the pos starter post & the ground(center wire) goes the the neg battery post or block ground.