Driving down highway at 60 mph and truck shut off. had to try to get it over to the shoulder to off the travel lane. Dealer found wire harness chaffed at front left shock tower ECM bracket. Several wires damaged, repaired and cleared codes. This could have been much worse had I been in heavy traffic and needed to cross additional lanes of traffic to park in a safe area. I had no power steering and limited space to park the truck. I called to police to have a car dispatched to park behind me so the truck could be loaded on a tow vehicle to bring it to the dealer. This could have been worse had my wife been driving.