In Michigan, with the proper axle spacing, you can gross 164,500 lbs. I pulled an "A" train, "B" train, and standard doubles for years.
An "A" train has two hitches on the back of a three axle lead trailer, (spaced about 5 ft. apart) which stops any whipping action. The two hitches are attaching a two axle dolly with a fifth wheel on it. The dolly can float up and down with rough terrain, but backs under the pup really easy, since it doesn't have the extra joint.(or pivot point)
A "B" train has a permanent fifth wheel on the back of a five axle lead and the dolly cannot "float" since the lead is all one solid frame with five axles under it. The fifth wheel is mounted over top of the back two axles on this five axle lead trailer. It backs easily under the pup also.
A stand set of doubles has a three axle tractor, three axle lead trailer, and a five axle pup.
11 axles is the most that you can have without a special permit. And when the front axle on each trailer is a 9 foot spread distance from the next closest axle, it adds 5,000 more pounds to your GVW. Which jacks your gross up to 164,500, with a big, wide front steer tire. We called them a "bologna" (ballony) steer tire.
I pulled these at 18 years old. This is a standard "gravel train".
This set can haul the extra 5,000 lbs. because of the nine foot spread on the pup.
This is a "B" train set of doubles with the 9 foot spread on each trailer. 154,000 lbs. gross.