I have not found the perfect travel trailer yet but after this weekend I have a question for everyone who tow with gasoline engines. When you are towing on interstate, for instance, running 70 mph in drive, what RPM's are you turning. I pulled my boat on the interstate this weekend and it weighs about 3200 pounds so I pull it overdrive just fine. I switched to drive just to see what it would like pulling a travel trailer, granted I was doing 75 mph, but it just seemed to rev the engine awful hard driving that fast in drive. So I guess my question is what is the fastest you tow in drive and is it working the engine too hard to cruise at 2900 - 3000 RPM's? Thanks to everyone for your advice!!