Smithco sx3 triple axle side dump trailer


SmithCo’s SX3 Three Axle side dump is a popular choice in states allowing extended gross weights for truck/trailer combinations with more than five axles. The SX3-4234 and SX3-4636 are the most common three axle trailer sizes but lengths run from SX3-3734 to SX3-5036.

Shorter to mid-length trailers tend to be used for everyday construction jobs, while the longer three axle trailers are frequently used for line-haul applications.


  • 37 to 50 foot frame lengths
  • Stockpile or windrow
  • Watertight; no leaks
  • Low load height
  • Dumps toward either side
  • AR400 Steel Tub, One Piece Floor
  • 80/100 KSI Steel Frames
  • Self-Aligning, Spherical Bearing Hinges
  • External Column Tub Supports
  • No Center Tub Divider
  • Shot Blast Paint Prep
  • Polyurethane Paint


SX Series Tub Capacities

34’ tub23 cu yd31 cu yd
36’ tub24 cu yd32 cu yd

Model SX3-4234 SmithCo Side Dump Trailer

Specs shown are for 41’ 5” frame length; other configurations available.

Frame Length 41’ 5”
Tub Length 34’
Width 102’
Height 8’ 3” at Tub side, 9’ 6” at Center
Tub Construction

1/4" Thick, AR400 Steel (or equivalent)

3/16" Thick, AR400 Steel (or equivalent) is Optional

External Column Supports, No Center Tub Divider

Frame Construction 80/100 KSI, Fabricated Steel I-Beam
Kingpin 2” Kingpin, 18” Setting, Replaceable Type
Landing Gear Two Speed, Non-Load Bearing
Bumper Push Bar Type, Bolt-On
Cylinders 3500 PSI, 5” bore
Hinges Self-Aligning, Spherical Bearing Type (greaseable)
Suspension Air Ride Suspension Standard Spring Ride Available
Axles (3) 25,000# capacity
Hubs 10 Hole, Hub Piloted
ABS 2S1M Anti-Lock Brake System
Drums Outboard Mount, Cast Steel
Wheels Steel Disc, 8.25 x 22.5 (12)
Tires 11 R 22.5 G Radial Tires (12)
Brakes 16 1/2” x 7”
Fenders Front & Rear, 1/4” Synthetic, 7 Degree Slope
Lights 12 Volt LED ICC w/Sealed Harness
Mud Flap (2) Polyline Anti-Spray Splash Guard w/ SmithCo name

Polyurethane, any combination of gray, white or black

Special colors available upon request

Minimum Tractor Hydraulic Requirements

25-30 GPM

2,600 - 2,800 PSI

10 Gallon Reservoir

Layout Options

SX3 Rear View
Model SX3 Rear
SX3 3734
Model SX3 3734
SX3 4234
Model SX3 4234
SX3 4436
Model SX3 4436
SX3 4636
Model SX3 4636