Dodge Ram Neil. It's a 2500 that we tow Guenevere with.

It gives me an indication of how hard the engine is working. The temp goes up when we are towing uphill, in the mountains. It drops when going down hill. At the same time we have a turbo boost gauge and a tranny temp gauge. All together they tell me how the truck is doing.

BUT, the truck does not have a water cooled exhaust. And we have never hit a point that I was concerned about the temp. Considering boats have water cooled exhaust, I don't think it would be worth the added cost. I just don't think you would get info that would help all that much. Many engines have an automatic hot temp shutoff, or cooling water temp gauge and I think this would be a much better indication of how it's doing.

Just my 2 cents worth.

Greg