Mounted valves

SmithCo works hand in hand with customers to make sure we’re giving them the right trailer for their needs. As part of the process, there are a number of choices that customers need to make to ensure their side dump trailer is the best possible fit for the job. This article series explains what customers should take into consideration when specing their trailer. See the series here.

Once our experts have collaborated with a customer to choose the right side dump trailer and tub style, the next step in the process of specing their trailer is determining the best placement of the hydraulic control valve. There are two options for customers: a truck-mounted valve, or a trailer-mounted valve. Consider the pros and cons below to think through the right choice for your situation.

Option 1: You operate just one truck for each side dump trailer:

You may prefer to have the valve mounted as part of your truck wet kit. This setup has the least number of parts/items between the control in the cab and the valve itself and is typically the most efficient and trouble-free setup.

Option 2: The number of trailers you use is not the same as the number of trucks you operate.

You may prefer to have the valve mounted on the trailer. Trailer-mounted valves can be operated from the cab by an air toggle valve, or an electric switch if the trailer is also equipped with an electric over air control box. Valves mounted in the trailer have more parts between the switch in the truck and the control valve, including air and/or electrical components.

Truck-Mounted Hydraulic Control ValveTrailer-Mounted Hydraulic Control Valve
  • Great for when you use just one truck for each side dump trailer
  • Less expensive
  • Efficient setup
  • Decreases troubleshooting time if there is a problem, since the only place you’ll need to investigate is the truck
  • Great for when the number of trailers is not the same as the number of trucks
  • Compatible with trucks that already have a wet kit and pull other hydraulically operated trailers; requires minimal changes to truck

  • Less flexible for situations where your truck pulls more than one hydraulically operated trailer
  • When troubleshooting, you may need to look at truck wiring, trailer wiring, or the air supply before locating the issue
  • Somewhat more expensive than mounting the valve on the truck

Special Considerations for Multiple Hydraulic Circuits

We can build your trailer with all the necessary valving installed on the trailer, so you only have electric switches installed in your cab, along with your wet kit. If preferred, some of the valving can be installed on the truck and be run via air toggle valves in the cab. The types of valves include multi-spool directional control valves, selector valves, counter-balance valves, and others as required to build you the trailer you want.

Trailer Valve Maintenance

No matter which placement you choose, maintenance on the valving installed on your truck or trailer should be performed regularly.

On a regular basis, ensure that your valves are:

  • Clean
  • As dry as possible
  • Properly lubricated

We recommend an occasional bit of air tool oil be added to the air shifter on the valve.

Important: Air line antifreeze should not be used for any of the trailer valves as it can react with the lubrication and causes seals and O-rings to dry out.

Your neighbor’s hydraulic valve placement may not be the one for you

Interestingly, we see regional trends in where our customers opt to place the hydraulic control valve. But we always work closely with customers to make sure they know both options, and that just because they’ve seen side dumps with one installation doesn’t mean that’s the best choice for their situation. It’s also reassuring to know the location of the valve can of course be adapted in the future if an operator’s situation changes.

Want to talk through the best choice for you? Call us at 800-779-8099 or get in touch on our contact page.

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