Lowboy Trailer Dimensions, Height & Weight

Straight answers, from people who spec lowboys for working fleets. A standard lowboy rides on a recessed well about 18 to 24 inches off the ground, runs 8 feet 6 inches wide and roughly 48 to 53 feet overall, and is rated by the ton — commonly 35 to 80-plus tons depending on how many axles are under it. Below are the numbers behind each of those, and the questions we get asked most.

Deck height & ground clearance

A lowboy's whole job is deck height: the recessed well rides about 18 to 24 inches off the ground, which is what lets you haul equipment up to roughly 11 to 12 feet tall and still clear the 13-foot-6 bridge law without an over-height permit. That low deck is the difference between a legal, no-permit move and a flagged, permitted one. Ground clearance is the trade-off — the same low well that keeps you legal is why you watch approaches, crowns, and railroad crossings.

How long, how wide, how tall (dimensions)

• Width: 8 feet 6 inches (102 inches) is the legal standard. Anything wider than the load or the trailer needs an over-width permit.
• Length: most lowboys run about 48 to 53 feet overall; the low well itself — the usable low deck — is typically 24 to 29 feet, with the rest taken up by the gooseneck and rear axle group.
• Loaded height: with an 18–24 inch deck you can carry machines up to roughly 11'6"–12' tall and stay under the common 13'6"–14' limit. Taller than that and you're into permits and route planning.

Weight capacity by axle (how the tonnage works)

Lowboys are rated in tons by class — you'll see 35-ton, 55-ton, and 80-ton units — but what a given trailer legally carries comes down to axle count. A two-axle lowboy carries roughly 40,000 pounds, a tri-axle runs 60,000 to 80,000 pounds, and adding jeeps and boosters is how you get to a legal 80-ton haul. Each added axle group spreads the load so you stay under per-axle weight laws instead of piling it all on two axles. Notations like "2-2-2" describe how many axles sit in each group along the combination — tractor, trailer, and the added jeeps or boosters — so you can match the setup to the weight you actually run. Western stocks lowboys across the common capacity classes — from roughly 35-ton up to 80-ton-plus — in XL Specialized, Alpha HD, and Choice, and we'll spec the axle configuration to your heaviest regular load, not just today's.

How you detach and load

A removable-gooseneck (RGN) lowboy detaches at the neck — hydraulically or mechanically — and the neck drops to the ground to make a low ramp so equipment drives straight onto the well. You reconnect and lift the neck before rolling. That drive-on loading is why crews with self-propelled iron (dozers, excavators, pavers) run RGNs. If you're deciding whether an RGN is the right buy for your fleet, that's a buying question — start with our RGN buying guide — this page is about the spec numbers.

What you can haul

Anything tall or heavy enough that a flatbed can't carry it legally: excavators, dozers, motor graders, cranes, drills, pavers, and large ag and industrial equipment. If the load tops about 10'2" on a flatbed or step deck, a lowboy is usually the answer — the low deck buys back the height.

Ready to match a lowboy to your loads? See what's on the yard: browse our lowboy inventory. Want the lowboy-vs-step-deck call first? Read lowboy vs. step deck.