Hydraulic Quick Couplings in the Transportation Market

April 3, 2024

Just like there are different types of rail cars for freight shipping, there are also different types of trucks and trailers used to transport goods and materials and provide services to consumers. These trucks and trailers utilize hydraulic quick disconnects.

Hydraulic Wet Kits and PTOs

The hydraulic quick disconnects used with trailers are found in the wet kit. Wet kits, also called wetline kits, consist of hydraulic hoses and fittings, reservoirs, filters, control valves, and pumps. Wet kits rely on power take-offs (PTO) to perform the trailer functions. The PTO turns the gear on a hydraulic pump. As the gears on the pump turn, it creates suction and pulls hydraulic oil out of the reservoir, allowing the hydraulic functions of the trailer to operate.

Types of Mobile Hydraulic Trucks and Trailers

The hydraulic wet kits described above are found on a variety of different mobile hydraulic trucks and trailers. Some examples include:

  • Dump Trailers
  • Roll Off Trailers
  • Propane Trailers
  • Side Dump Trailers
  • Walking Floor Trailers
  • Ejector Trailers
  • Live Bottom Trailers
  • Detachable Gooseneck Trailers
  • Snow Plows and Salt Spreaders
  • Garbage Trucks

dump truck at grain pilehttps://www.istockphoto.com/photo/unloading-grain-truck-gm172186077-3135208?phrase=dumping+grain

Dump Trailer

Dump trailers are available as single-body and tandem. The hydraulic system raises a hoist to dump the product out of the trailer. The hydraulic pressure is supplied by the PTO. Hydraulic quick disconnects are used to connect the tractor to the trailer.

roll off trailer

https://www.istockphoto.com/photo/recycling-center-with-unloading-truck-gm172975935-7211744?clarity=false Credit:buzbuzzer

Roll Off Trailer

A roll-off trailer is designed to carry wheeled open-top containers. The PTO raises the hoist to lift the trailer and roll the container off. Wingstyle couplings are typically used on roll-off trailers.

propane truck

Propane Trailer

Hydraulics are used to unload and pump off propane from the propane trailer. A PTO is used to drive the pump system. The pressure side uses 1” wingstyle quick disconnects, and the return side uses 1-1/4”.

Side Dump Trailer

The cargo on a side dump trailer is unloaded by tilting the right or left side of the trailer. They are best suited for building roads, stockpile dumps, excavation/pit mining, semi-liquids, and fine materials. Wingstyle and ISO-A couplings are typically used on side dump trailers.

Walking Floor Trailer

If a freight trailer can’t back up to a loading dock, or it’s not safe for a forklift to drive onto the trailer, a walking floor trailer is used. This allows freight to be slowly moved to the back of the trailer to make it easier for the forklift to access and unload the goods and materials. Wingstyle, ISO-A, and European standard couplings are used on walking floor trailers.

Ejector Trailer

An ejector trailer is used where a traditional dump trailer would be prone to tipping, such as a location with unstable ground. Paper mills and mulch plants are good examples of places to use ejector trailers.

Live Bottom Trailer

With a live bottom trailer, the PTO essentially drives hydraulic tubing alongside the trailer to the motor on the back end that turns a conveyor system to offload the product. 

gooseneck trailerhttps://www.istockphoto.com/photo/huge-classic-industrial-semi-trailer-carrying-heavy-commercial-oversized-cargo-gm1386575811-444771671?clarity=false Credit:Alexander Lyakhovskiy

Detachable Gooseneck

Also called lowboys or drop decks, detachable gooseneck trailers have a low center of gravity which makes it easier to load and unload equipment. Wingstyle couplings are commonly used on these types of trailers, along with additional hydraulic connections to connect jacks for loading and unloading.

snow plow salt spreaderhttps://www.istockphoto.com/photo/salting-highway-maintenance-snow-plow-truck-on-snowy-road-in-action-gm1222252406-358592555?clarity=false Credit:Milan Krasula

Snow Plow and Salt Spreader

Snow plows and salt spreaders also utilize hydraulic quick disconnects on municipal trucks or small city trucks to connect the plow or the spreader and wings. This is done with ISO-A and ISO-B fittings, or ag-style couplings commonly used on tractors. In recent years there has been a movement to stainless steel quick disconnect couplings on snow plows and salt spreaders. Stainless steel offers durability and corrosion resistance, which helps couplings last more than one year when subjected to harsh weather conditions.

garbage truckhttps://www.istockphoto.com/photo/garbage-truck-ca-gm1315290086-403302111?clarity=false Credit:Salameh dibaei

Garbage Truck

Garbage trucks also use quick disconnects. Garbage truck operators keep spare hoses on the truck with quick disconnects to change out the fittings. This is a preventative maintenance measure to keep trucks running without having to stop and go to a hydraulic store to purchase JIC fittings.

Dixon Quick Disconnects

Dixon offers a wide range of quick disconnects for hydraulic mobile trucks and trailers to ensure you have The Right Connection®.

W-Series Wingstyle


The W-Series wingstyle connection is available as a female threaded coupler, a hex-nut female threaded coupler, and a female threaded plug. The couplers come in 1/4” to 1-1/2” sizes with a brass body and a steel wing nut or hex nut. The innovative hybrid valve design provides industry-leading flow and pressure performance. There is a full hex on both bodies for easy installation. The black O-ring on the plug serves as a connection indicator. The couplings are not fully connected until the black O-ring is not visible, which allows the valve to fully open. 

Watch this video for a quick look at the features and flow characteristics of Dixon’s W-Series quick disconnect couplings.


W-Series Wingstyle Dust Cap and Dust Plug

W-series dust cap and plugDust caps and dust plugs are recommended for wet line connections. Hydraulic quick disconnects are the No. 1 contamination point of a hydraulic system. Using a dust cap or plug keeps the coupling clean and prevents contamination, which keeps the overall hydraulic system in good shape.



Dixon’s K-Series are interchangeable with the Parker 6600-Series, Faster ANV-Series, and Danfoss 5600. K-Series couplings meet or exceed ISO7241 Series ‘A’ performance requirements. They are available in sizes 1/4” to 2” with rugged steel construction and Trivalent Chrome plating to maximize durability and service life.



Dixon’s H-Series couplings are interchangeable with the Parker 60-Series, Danfoss/Hansen HK-Series, and Faster HNV-Series. Standardized product variations are available to meet the requirements of slide-gate, food service, and steam applications. The H-Series couplings meet or exceed ISO7241 Series ‘B’ performance requirements. They are available in sizes 1/8” to 2-1/2”, and come in a variety of material choices, including steel, brass, 303 stainless steel, and 316 stainless steel.


Quick disconnect couplings are advantageous in a variety of applications, including on mobile hydraulic trucks and trailers. Dixon’s 12 U.S. distribution centers have the quick disconnect couplings you need in stock and ready to ship. For more information, visit dixonvalve.com or call 877.963.4966.