Uncoupling order, lowering landing gear and air bag suspension?

You leave the legs up off the ground some to prevent a high hook. It causes the trailer to be lower than the truck when you couple up the next time, because the truck will lift the trailer.

A high hook is when the trailer isn't sitting flat on the fifth wheel, and there is a gap. It means the kingpin is also not locked in correctly. High hooks can often pass a tug test, and go quite a few miles. Until they feel like coming loose and your trailer goes skidding off wherever it feels like.

 

Pigtail is the wiring harness. It's curled up like a pig's tail.

 

If you drop it too high, the pin can also jump the fifth wheel, and end up in front of it. Then you play hell trying to get it back where it needs to be.
I always drop the landing gear, loaded or empty trailer, to about an inch off the ground. That way just about any tractor can grab it, and the landing gear doesn't get jammed, where you can't turn the handle.

 

OP, part of why you dump the bags is so when you pull out from under the trailer, they don't shoot upwards and possibly damage the shocks and bags. When you dump them, there's no chance of that happening, and it also lowers the trailer down to the ground nice and gentle.

 

My opinion will not be popular. Nor is it taught. First thing I do outside of the little things when your ready to start un hooking. Disconnect Glad hands and 7 way. You will never rip them off if its your first thing.

 

Wow. Stupidest thing I ever heard....

 

They will teach you all of this in school however as said Before couple and uncouple THE EXACT Same way each and every time and you won’t have issues