Tandem placement and turning radius

I know that dumping the air bags will lower the fifth wheel, but if I am trying to back under an excessively low trailer, I will get out and crank on the dolly to raise the trailer up. Why? I can get more precision cranking the dolly than from dumping the air bags. If I only need to get one extra inch, I can get one extra inch by cranking the dolly. If I dump the air bags, I lower the fifth wheel about 4 to 6 inches. Dumping the air bags is an all-or-nothing thing.

 

Back under the trailer WHILE the bags are dumping the air.

 

The trick is to use the inflation time when reinflating the bags. Drop bags, back under trailer but keep kingpin clear of jaws, hit dump switch to reinflate bags and as soon as the 5th wheel is flat against upper coupler, back the rest of the way and latch. This let's you latch without the full trailer weight on the 5th wheel plate.