300-TON HAULER WAS STUCK ON STOCKPILE. EE'S CONNECTED COAL HAULER TO A RUBBER TIRE DOZER WITH A 1 1/2"" CABLE SLING. EE IN THE DOZER AND EE IN THE HAULER BEGAN TO ACCELERATE. AS THE MACHINES STARTED MOVING FORWARD THE HAULER TRAILER LAID OVER ON ITS SIDE. THIS ALLOWED THE TRAILER TO DISCONNECT FROM THE TRACTOR ALLOWING THE TRACTORTO PROPEL FORWARD STRIKING THE DOZER.