I picked up my coach today at the local CAT dealer. When they put in shop they tested for codes found that yes it had been overheating and all hoses, thermostats, fan rotation, speed and direction were correct. When they inspected the side radiator system they found it completely clogged up. You can't see this condition from road side. They put a special solution on it then steamed it and then used a special pressure washer, so as to not damage fins, and blew it out. They test drove for 50 miles on grades and it ran at 200 (normal for a C7 350 HP) and outside air was well over 100. Picked it up today and ran it to storage and it ran at or below 200. They said at least once a year this needs to be addressed on side draft radiators. Power wise they advised the C7 was at peak power and that re-ehausting or chipping it would not be of benefit for more power, just FYI. Now if I could just get the dash air to work good...
