OK so am going thru the new to me 5ver since being used you don't really know,Its my 1st trailer of any size anyways and the first with brakes, My sprinter has two axles and while I was packing bearin...
If you are under the spring at the axle you should be fine. The risk of jacking on the axle is bending the axle. The axle tube is not designed to carry the weight of the trailer - the springs are.