If the transmission requies a rebuild that will cost about $1,500.00. The weight of your trailer should be within the two limits of the truck. A cooler is a very good idea. Take the truck to a Ford dealer and have them look up the ratio of your differential and make a reccomendation for towing. Going to a lower ratio will seriously drop fuel economy but your low milage make make that acceptable. BTW, a differential replacement will run $1000.00 to $1,500.00. That has to be factored in. As for towing the camper, I have had many friends experience engine/trans. failure even when the weight was well within the (theoretical) limits of the truck. What happens is that the air drag exerts tremendous forces that take the 'pull' weight way-way beyond the actual weight of the trailer. Whatever you do, for the short trip, keep you speed at no more than 55 mph. I don't know what kind of trailer you have, but look at it this way, you are trying to pull an 8' to 12' high wall through the air at highway speeds.
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