Standard size and weight limits for a typical tractor and trailer?

The weight limits are based on how many axles you have. and how much you want to pay for the license. The more weight the more a license costs.

Trailers are limited to 53ft max

A single axle can have 12,000 lbs max (a single tire on each side as in the steering axle)

A single axle with 4 tires (2 each side) is rated at 20,000 lbs.

Tandem axles, two axles within 5 ft of each other 36,000 lbs

Axles separated by more then 5 ft are rated as single axles.

So if a tractor has a steering axle 12K
tandem driver axles 36k
tandem trailer axles 36k
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total 80k


A 28ft trailer is called a pup
The equipment that goes between 2 trailers to make a set is called a dolly

2 trailers + a dolly can not exceed 61 ft. ( 28 + 28 + 5) end to end (tractor not counted)

A rough rule of thumb for weight you can load is trailer length minus 2 ft in thousands.
So a 28ft trailer can be loaded 26,000 lbs if loaded perfectly.