What is the difference between a SRW & a DRW? Possibly this is. Notice that the truck is not still attached to the trailer. The DRW truck had the extra stability & stayed upright. The truck remained upright & on the road. The trailer tore out of the truck & barrel rolled down the embankment.
Sure any SRW can pull a big 5er. You don't need a DRW till that split second when you really NEED that DRW. That is when your life just might depend on those extra two wheels.
Notice also what the kingpin did to the 18,000lb hitch when it broke out of the truck. Trailer weight at the time of the blowover was less than 13,000 lb.
Click For Full-Size Image.
Click For Full-Size Image.
