2007 Freightliner Columbia with a 60 series Shutting down, stumped!

I have a 2007 Freightliner Columbia with a 60 series with a auto trans/with clutch. I’m a farmer and this is my semi I use to haul all of my gain from field to farm and farm to grain elevator. I’m not a master technician by any means but I’ve been doing a lot of my own tech work on farm equipment for 10 years after finishing an Agricultural Technology Mechanics school and I have basic to moderate diagnostic skills in electrical work.

My problems all started on my first load of grain this September when the truck would stall out(cel/sel came on briefly, lost throttle for 1-2 seconds) and then the throttle came back and lights shut off like nothing ever happened. Then a couple of weeks later the problem started evolving or getting worse or I have another problem. Going down the road the truck loses all power(gauges all go to 7 o’clock then sweep clockwise and back and engine shuts down and no sel/cel or any lights appear on my dash) and I just coast to a stop, I wait a couple minutes and cycle the key every few seconds or minute till I see the cel/sel and I start the truck right up and take off again.

I’ve taken this truck to stoops Freightliner and spent a couple thousand in diagnostic time and on drive time and they’ve let to find anything. Here are all the things I’ve fixed or replaced or checked or tried. The worst part about any of this is that it’s not storing any codes before or after the shutdown.
Swapped ECM’s with a known working truck ecm off exact set up,
Cleaned all of the connections for the ECM’s and sensors I’ve replaced,
Changed out the Cam Sensor,
Changed out the Crank Sensor,
Changed out all the batteries for new ones,
Changed out barometric pressure sensor that runs EGR,
Cleaned grounds and replaced terminals for many of the grounds,
Replaced the ignition relays infront of passenger seat under dash, checked for power at ecm in all 4 pins tht have 12v from battery all the time.

My local shop has spent two days tracing wires and connections and we are at a stand still. Any help is good help, call or text me(Tyler) 7658943009 or reply here. If you fix my truck I’ll make it right with you no matter where you’re at.

 

Someone suggested that but I haven’t tried that yet, I will try that.

 

I’ve inquired about that and mine doesn’t have the engine relays, some do and some don’t depending on what they came with. I was told IF mine had them they would be in front right side of firewall under hood in an electrical compartment and mine doesn’t have any electrical boxes under the hood besides harnesses.