cahillprc2 wrote:
1) are the X-chocks really necessary,
No, certainly not
necessary but they do help minimize suspension wiggle when someone is walking around inside the camper by preventing the tires from rotating on their axis. Does nothing though for side to side or up / down suspension movement.
2) Do most people use just the X-chocks.
FAR too many do, ignoring the manufacturer's own instructions to not use BAL X-Chocks as a "parking brake", or in other words to not use them to actually chock the trailer to prevent it from shifting or rolling away. The reason is that tires shrink as they cool so X-Chocks if installed when you first arrive on site will loosen as the tires cool, potentially allowing the trailer to inadvertently shift. :E Here's the note from Norco included in every box of X-Chocks ...
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This how I properly secure my own dual axle trailer ...
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Minimal suspension wiggle and it's not going anywhere, regardless of campsite slope. :B