TRIPLE - DUAL WHEEL GOOSENECK

Model: FMAX312

With up to a 40,000lb GWVR, 18” Engineered Beam frame, and 9,000lb curb weight, the FMAX312 is indisputably the king of the road.

Build Your Own Trailer

Engineered to Deliver

We design, engineer, and build our own I-Beams. Our U.S. Patent Protected Engineered Beam design allows us to have an almost infinite control over the shape of the beams. We’re able to optimize the performance of the steel by putting it to work where we need it most. No dead weight. No added reinforcements needed. Our beams are the tallest and strongest in gooseneck trailers, with the best strength-to-weight ratios on the road.

Fleetneck Logo

FMAX312

Diamond C FMAX312 Fleetneck Engineered Beam Gooseneck Trailer

Standard Features

30,000 lb GVWR. Choose from 25′ – 44′ length. Features a 16″ or 18″ Low Profile Engineered Beam Frame and 3 – 12,000 lb Lippert Axles.

FMAX216 Air Ride Suspension

Upgrades

Popular upgrades include: Deck on the Neck, Sway Control, and Air Ride Suspension. Choose between Max Ramps, 12′ Hydraulic Dovetail, or Straight Deck with Ramps.

FMAX Overview Diagram
  1. The Neck – Curves distribute force throughout the neck so there is no concentration of stress in corners like traditional goosenecks.
  2. The Deck – It’s low profile for easy access. Tire-covers are HD 3/16” diamond plate. Boards are capped at each end of the deck for added durability.
  3. The Camber – The deck and frame have a slight camber when not loaded. When loaded, it flexes as necessary to level but never sags like traditional goosenecks.
  4. The Lace-rail – Channel-Iron for durability and versatility with no notches or cut-outs for maximum strength. Includes stake-pockets and pipe-spools.
  5. The Box – It’s big and roomy. The lid is curved for added rigidity and gas spring assisted for easy operation.
  6. The Steps – The retractable front deck steps solve the common issue of traditional front deck steps being bent in low clearance situations. The mid-deck side turn signal step makes for easy access when equipment is loaded.
  7. The I-Beams – We engineer the beams, optimize them, and build them for each trailer configuration just like semi trailer manufacturers have been for decades. Our I-beam frames are taller, stronger, and lighter than your neighbor’s. 14-18” tall. Standard steel bends at 36 ksi. Our beams are built using steel rated at 50 ksi minimum.

Fleetneck Engineered Beam

Thank you for considering a Fleetneck. We respect the money that you’ll spend on a gooseneck trailer and yearn to make sure that our trailer is one that takes good care of you for years to come.

12' Hydraulic Dovetail

12’ long with easy to climb, 12.5 degree approach angle. Blackwood rubber-infused runners for traction. Automatic latch for easy operation. Includes wireless remote control.

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Sheffield Financial Logo

Finance Your Trailer

Finance a brand new FMAX312 with interest rates as low as 6.99% through our financing partner Sheffield Financial.

Diamond C Warranty Logo

Quality You Can Trust

Every Diamond C Trailer comes with an industry leading 3 year warranty. We are proud of our trailers and stand by them. Find out more here.

Fleetneck Style

Choose Tail Style:

Max Ramps

44” wide ramps for MAX versatility. 50 ksi steel ramp frames x 4 frames per ramp for MAX strength. HD Spring loaded for easy lifting from deck and from ground. For safe, stable loading.

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12' Hydraulic Dovetail

12’ long with easy to climb, 12.5 degree approach angle. Blackwood rubber-infused runners for traction. Automatic latch for easy operation. Includes wireless remote control.

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Straight Deck

Includes 96" Rear Slide-In Ramps (3" Channel). Single piece bumper with light protection.

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Length/Width

GVWR

Includes 40K Adjustable Coupler and Frame/Neck Reinforcements

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Ramps

Dove

12' Fully Automatic

12.5 degree load angle with Blackwood infused lumber included.

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Jack

2 - 12,000 lb Drop-Leg Jacks

Two heavy duty, square, drop-leg trailer jacks with a side-wind handles. Constructed of engineered alloys for enhanced strength, stability and side-load capability.

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2 - 12,000 lb Hydraulic JacksClose
2 - 12,000 lb Hydraulic Jacks w/ Hydraulic DovetailClose

Battery/Charger

Optional w/ Hydraulic Dove or Jack options

Paint Type

DM Difference Maker Coating System Logo

We partnered with Sherwin Williams to develop our own custom designed powder coat finishing system that provides long-lasting, rugged, and beautiful trailer finishes.

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Special Color Logo

Choose from a variety of our Special Colors below, or enter your own custom color of choice.

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Paint Color

Axles

Brakes

Frame

16Close
18Close

Cross-Members

Floor

2

Installed after painting to ensure no framing is left unfinished. Floor is secured with 5/16" screws and a bolt-on board cap.

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Blackwood Lumber Outer

Blackwood is rubber infused, pressure treated pine flooring that provides enhanced traction in the wettest conditions, outstanding impact resistance in the toughest environments, and increased flooring lifespan from its no fade, no crack technology.

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Blackwood Lumber Full

Blackwood is rubber infused, pressure treated pine flooring that provides enhanced traction in the wettest conditions, outstanding impact resistance in the toughest environments, and increased flooring lifespan from its no fade, no crack technology.

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(On Every Cross-Member)

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Neck

Coupler

30,000 lb Bulldog BX1

Round Adjustable

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30,000 lb Bulldog Square Load Leveler

Heavy-duty, high-strength, steel construction with an easy to use vertical adjustment design for a quick and secure connection on the road.

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Shocker Hitch Air Ride Coupler

Air Ride towing for a smoother, safer ride. Shocker Hitch helps to eliminate the jerks felt when towing on rough roads by directing the tow resistance through an airbag, producing a smooth ride. Utilizes the BX1 Coupler.

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King-Pin Adapter

(Round Adjustable)

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Storage

Chain Tray

(In Top of Neck)

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Deck on the Neck

Bolt-on Deck on the Neck

7' x 8' Bolt-on Deck with Clearance Lights

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Weld-on Deck on the Neck

7' x 8' Weld-on Deck with Clearance Lights

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Lace Rail

Tie Downs

Stake Pockets

Slide Track & Ratchets

Full Length Slide Track (passenger side)

(Includes 2 welded ratchets between wheels)

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Full Length Slide Track (driver side)

(Includes 2 welded ratchets between wheels)

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Steps

(on rear of trailer)

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Wiring

Lights

All LED Lights

Waterproof, all rubber-mounted, impact resistant, wired with a heavy duty wiring harness.

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Sway Control

Winch

Winch Mounting Plate w/ Receiver Tube

(In Top of Neck. Not Applicable w/ Chain Tray)

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12K Warrior Winch Box Package

Includes battery, 5amp charger, and winch mounting plate.

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17.5K Warrior Winch Box Package

Includes battery, 5amp charger, and winch mounting plate.

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Tire Size

Wheel Color

Spare Mount

Spare Wheel Color

Spare Tire Size

Suspension

Air Ride Suspension w/Lift AxleClose