I would like to add my two cents regarding overheating in a class A Motorhome. A couple of years ago while driving on I-5 south bound near Bakersfield CA suddenly I discovered the heat gauge went off the scale,steam everywhere. What led up to this was the fact that the old familiar noisy radiator clutch fan had been silent for a few miles and the heat was building up in the engine and it blew an over looked rubber hose that goes from the water pump to the intake manifold just a little hose that appeared to be o.k. when all the others were replaced it wasn't.I did not look for the obvious and I assumed it was a freeze plug because the steam and water seemed to come from the side of the block.I had us towed in and it was just a big mess all around with loss time and etc. Lessoned learned is obvious. Those clutch fans are a nuisense when they come on because they are so noisy but watch out if they don't. This was on a 454 engine by the way and the second clutch I went thru in three years.