Well thanks for all the info on the Ford V-10 engines, I have done some more checking since I posted, and the Ford dealers here in cental wa will only repair by replacing the whole head aat a cost of about $3000. They will send you to a repair shop that will repair problem but no guarantee. So the reasons for this post is there such a list that will tell me which manufactors and which model class a comes with a 454 chev engine? This would save some time in my hunting to the right motorhome. Thanks again Patrick