Why did the rear bumper get lower when I slid the tandems back to the rear of the trailer?

How to slide your tandems

 

Possibly it had something to do with the angle of the pavement in the dock itself?

 

Let's play what if:

What if the fifth wheel height is lower than the height of the fifth wheel plate when the trailer is setting perfectly level?
What if the air in the tractor suspension was dumped and the trailer wasn't?
What if there was a bit of a down slope to the dock behind the drive tires?

Just a few things to ponder.

 

Trailer tandems are probably sitting in a low spot now. A spot that has been worn into the surface from the tandems of other trailers being pushed into the ground by the weight of forklifts or other what if’s.

 

Or if you have a flat tire on the left front drive axle, inside tire, or would that make a difference if the right rear outside drive tire was only half full?
Wow the things that make you go hhmmm!!

 

Can't forget pushing against a trailer (with air ride) that has the brakes set will raise the back end.

Trailer may have been hanging from the dock bumpers if pushed up against them and pinned there by the tractor.

 

There are a lot of what ifs, that's for sure.

 

Yeah well that ship sailed before I started driving lmao