trailer shake

Before unhitching from truck I run front land gear legs down so that when I pull the snap pins the inner tubes aren't extending as much.

After unhitching I raise/lower landing gear legs to level front to rear then I drop front legs 1". Then I run rear stabilizers down and use 6X6 block under the pads so stabilizers have as wide of a stance as possible. Then I run the stabilizers down tight.

Then raise front legs back up to level.

The wide stance of rear stabilizers, the tightness of the stabilizers from loading them with front legs, the front leg inner tubes not being extend much all help to make our 5vr solid.
There is still some bounce because of rubber tires/springs. If that little bit of bounce is bothersome.......get a couple of screw type jack stands and place them in front or rear of wheels and screw them up tight.

As long as it sits on rubber tires it is going to shake. get the corner stabalizers as tight as possible. maybe put a board under them because they always sink into the ground. And get used to it.

I installed some DIY JT Strong arms. Four on the front and one diagonally on the rear. Took most all of the shake out. On black top it's solid. Dirt or gravel it's still pretty good. Next up is some Bal Chocks.

Winfield RV Stabilizers Not that expensive and with the use of a good set of wheel chocks. Works really well.

I added a set for stabilizer jacks just forward of the wheels and a BAL Twin Pin Stabilizing Jack to the king pin. No more movement.

I have found that a lot of shaking comes from the "landing gear legs". If you pull the pin and drop legs, just before contact with ground, wiggle end at plate and you can see how much movement there is. What I do is once plate is in contact with ground, and there is a little weight on leg, I push one leg out and back and the other out and forward. This seems to help with shaking for me. Not a cure all, but it does help.