If I understand what you're asking, I'd think you'd want the thicker end of the Andersen on the slope end in a duel directional slope if that makes sense.
I love those chocks,,,,but,,,, Some times , in loose gravel situations. if you find them dragging when trying to get on them, unplug your trailer brakes so they are not working with the truck brakes. Found that out the hard way!!
Hah! I DID! And it all made sense then! Curious how trailer brakes affect the slipping. When you are pulling onto them, do you keep your foot on the brake? I have encountered slipping too, especially if there's some mud under them, like it always seems to be at the end of my driveway.
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2019 Rockwood Geo Pro G19FD w/off road package
2015 Ford F150 XLT Super Cab 4x4 V8 Yes, I drink the water!