New 2019 TRDOR DCLB - vibration from rear end from bumps?

As stated in the title, I just bought a brand new 2019 TRD Off Road DCLB. I love a lot of the truck already, but one thing I'm noticing is that I get a lot of vibration (almost shaking) whenever the rear axle goes over even the smallest bumps. I know the ride of a body on frame truck is going to be a little bumpier than a standard car, but it almost seems like the rear end is overly sensitive to bumps. I mention the rear end specifically because the front end by comparison feels very damp and rolls over bumps in the road without much movement in the body. However, when the rear end goes over the same bump, I get a lot of vibration coming back through the vehicle.

Is this possibly a weight distribution issue (i.e since the rear axle has less weight over it, it can't dampen as well)?

Truck is still very young (only 160 miles on the clock as of this morning) and I have not modified anything on it.

 

Rear is solid axle - front is not. Body on frame has a lot to do with it too if you’re not used to it

And yes, not having weight back there doesn’t help

 

Light weight truck box. Go get a load of mulch, or try lowering the air pressure a few lbs. I haven't done this on my Tacoma, as I haven't felt the need, but I have done this on every company truck I've had, they're all full size, and some 3/4 and 1 tons.