Belly loading a sagging stretch trailer?

Most of the stretch loads I’ve done have been pretty much solid, a few 100’ foot beams have sag some even with dunnage on the ends. But by not a lot.

 

Your right. Stretch rgn, the weight is in the well...not atop the 5th wheel and rear suspension.

 

I have used / pulled many different stretch flats most of them are what I would call twist-o-flex trailers.
Even when they are new there not much better. If you load an 80 ft stretch flat with 40000 lbs of 80 ft rail road rail even with the semi rigidity of the rail and a new trailer you still have a sway back horse. Now as far as RGNs go I had a 60 T Trail King 28 ft well / w 20 ft stretch 3axle 4th flip it was 12 yrs old it did sag a little but not near as bad that it would bounce and hit the ground. I never belly loaded it either. Bad habit I always thought.