Slide?

 

My boat was 21 ft, trailer was probably 30ft. Hydraulic surge brakes so the brakes were not an issue. It would get a little unstable over 65 mph, but as long as you did not try to tow fast it was no problem. Towing Discos was more weight and more air drag, but still handled it fine. No problem with temps except on long uphill grades - engine cooling gave up before the trans did, have had to pull over to let the engine cool, never any indication the trans was getting too hot.