The stabilizers aren't to be used to level the RV. Neither are the scissor jacks.
It's not the device that's the issue it's the stresses you put on the frame if you try and level using the corners. You should set up level sitting on the tires then snug the stabilizers or scissor jacks to the ground/pad.
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Salem 29RKSS Pushing a GMC Sierra 2500HD!
Gotta go campin!
Just changed out the 4 cheapo stabilzers for Bal scissor jacks. Added 2 more in the middle for extra stability. Camping World had a sale on the deluxe 24002d rated at 7500 pounds. We could have gotten by with the 5000 lb jack, but these were on sale at the time for $60 a pair. Got self taping screws and they installed easily. Thinking about having them welded, mainly so they can't walk away. Here's the Bal link:
Here is what I installed with bolts and lock nuts. I would only get jacks that have the 3/4 inch adapter so I can raise and lower in a snap with my drill. See pics