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Originally Posted by momszoo2
This is the trailer I have. 1970 OVERLANDER INTERNATIONAL LY 27 DOUBLE
4575 465 19
My sub is 2 wheel drive
My coach, while 8 years older, is quite similar to yours with a factory stated dry weight of 3,940 pounds with an empty hitch weight of 405 pounds. In reality, my coach which was heavily optioned by the original owners had an, as delivered, empty weight of 4,440 pounds with a tongue weight of 550 pounds. When loaded for an extended vacation, the weight of the coach varies between 6,000 and 6,100 pounds and the hitch weight stays fairly constant at 725 to 750 pounds. I do have twin 40 pound Worthington Aluminum LP cylinders on the hitch rather than the more typical 30 pound cylinders.
My usual tow vehicle is a 1999 K2500 Suburban (3/4-ton with automatic four wheel drive). From 1995 when I towed with a 1995 K-1500 Z71 Club Cab pickup with 5.7 liter, until my first long trip with the Suburban in 1998 I towed with 1,000 pound weight distribution bars. During the prior 31 years, the coach had been used extensively and didn't have any popped rivets nor any cracks in the skin (had always been towed by a full-size Mercury or Oldsmobile coupe). Upon my arrival in Boise, Idaho for the WBCCI International Rally, I had a crack in the aluminum over the entry door; and upon further examination found close to two dozen popped rivets on the interior. A knowledgable Airstream hitch installer inspected my hitch and immediately suggested that I go with 600 pound weight distribution bars due to my firmly sprung tow vehicle. After making those repairs, the crack stopped growing and popped rivets became an infrequent experience. The axles on my coach are original, and still have a down angle on the torsion bars but are very near the point where they will have to be replaced.
Particularly if you choose to use a Reese Strait-Line hitch, I would suggest considering 600 pound weight distribution bars. If you aren't familiar with the Resse Strait-Line hitch, the photo below shows the setup on my Argosy Minuet 6.0 Metre when it is towed with my '75 Cadillac Eldorado.
The weight distribution bars in the photo above are the 500 pound bars that the original owner used to tow the Minuet with his 1978 Ford LTD sedan.
Good luck with your investigation!