Why do they have doubles and triples ?

I agree, I ran for Yellow many yrs ago, they were very easy to pull, excellent for tight turns, the driver knows not to pull in where backing much more than 20-30' would be needed to get out! I loved pulling pups, only drawback I saw was hand pulling a dolly over snow as it was a b-t-h to do by yourself on a closed satellite yard in the middle of the night! The only other real issue was wiggle waggons on slick roads with heavy cross winds.....dangerous!

 

I pulled doubles while hauling grapes seasonally for the winery. In my opinion, they are easier to handle than a 53' trailer. Take your turns 10mph slower than the posted speed , because of the wiggly back trailer. You have 2 points of pivot on a set of doubles, so unlike a 53' dry trailer, you don't actually have to turn as wide as a 53' trailer.

 

I love pulling doubles.Ive passed up many wagon loads so I could hook to a set...except in the winter is the only time Ill consider a 53.

But another major reason for doubles in LTL companies is the fact that it there are usually multiple shipments on one pup, going to different places. Unless you are running it direct, it usually has to get broken at the reship(hub)..So instead of having to break 1 53, you can break two pups at the same time. And if the trailers are built by region, you can put that trailer in a sector that handles freight fora particular region instead of having to drive one skid from one end of the dock to the other..Speed and effienciency are big in cross- docking. Freight needs to be moved quickly from its inbound to its outbound trailer so the freight can be on its way to the customer.