grounds check all grounds just went thru this with a 04 2500 hd 6.0 replaced the power steering pump and did a tune up was working great returned it to my buddy put the plow on it went to leave his lot to give me a lift home and blah cut right out in middle of the street.spent the next week chasing the problem.there are a small group of grounds on the left side of truck at the rear cab mount start there make sure the surface is clean where they are attached,also some at the front cab mount same thing there make sure the eyelets are good to the wire not broken under the coating on wire,also the ones to the back of the engine large braided one and some have one on pass rear of the block hope that helps