You can probably find information on the Airstream forum or other travel trailer site. Many Airstream dealerships install the Equalizer and they are a very good hitch. I have a 23' Airstream, 730 lb. on the tongue and about 5500 lbs. to pull down the road.
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If the trailer you're going to pull is 4500 lbs. is it single or tandem axle? Either way, with that much weight I think you're going to need to distribute some of that weight and you'll need the anti-sway if you have a single axle trailer.
I have used only the Equalizer and it does a very good job. All of them take some getting used to, but once you've had some experience you can get it all hooked up quickly and fairly easily.
Check out the Airstream forum and use their search tool to search on
"Anderson hitch"
Linear Mode
