Which is Correct?

its own axle and wheels.

Let’s look at the position of the heavy box in the trailer in the image.

The box represents the main load, which concentrates most of the weight.

Its position matters a lot.

The best and safest position is to place the main weight in the center of the trailer, right over the axle.

When the heavy weight is over the trailer’s axle, it is fully supported by the trailer’s wheels.

This is the central point.

It doesn’t tip the front up or the back up.