53 foot regular spread vs 48 foot spread tandems

Illustrates difference between 2 commonly used tandem axle trailers.

Which is better – 53′ trailer with regular spread or 48′ trailer with 10’1″ spread tandems?

There is sometimes confusion the difference between regular and spread tandems, how they are used, and what trailer lengths are used with each.

To help clear this up, let’s take a look at comparing two common setups:

  • A 5 axle semi truck with a 53′ trailer and regular tandems – 4’2″
  • A 5 axle semi truck with a 48′ trailer and spread tandems – 10’1″

To understand where each of these trailers can be operated, let’s take a look at restrictions that are commonly put on both of these trailers.

State kingpin restrictions:

  • 53′ trailer length – applies
  • 48′ trailer length – do not apply in USA

US Federal Law Tandem weight restriction:

  • 53′ regular- 34,000 lbs
  • 48′ spread – 40,000 lbs

Western Canada Tandem weight limit:

  • 53′ regular – 17,000 kgs
  • 48′ spread – 9,100 kgs

Overall US Federal gross weight:

  • 53′ regular – 80,000 lbs
  • 48′ spread – 80,000 lbs

These differences lend themselves to differences in where these trailers are used. 48′ spread trailers are more flexible to use due to the differences mentioned above, you can have a higher axle weight and you don’t have to worry about kingpin distances. But you lose a few feet of cargo space. This leads them to be used commonly in the flatbed industry where goods are generally heavier and a few feet of deck loss isn’t that much of a big deal. Another use that we’ve seen is for general freight in California because of CA’s very restrictive kingpin law.