Restoring antique dump trucks and similar industrial and commercial vehicles is fairly straightforward, with many of the steps being fairly easy to understand and complete with a knowledge of restoring cars and trucks in general. However, one place where this knowledge will undoubtedly fall short is in restoring the hydraulic system used to raise the bed of the truck. For this step in the process, you're going to need some specialized knowledge and take great care in the restoration, as this is the kind of repair that can make a restoration job much more authentic. 

Looking for the Original Part

Dump trucks are more rarely restored than muscle cars and other passenger vehicles, so the market for replacement parts for these machines is simply more limited. If you're restoring a very popular model, then you may be able to put in a special request at a well-connected catalog of parts or a dealer for vintage models of the make you're restoring. A trip to the local junkyard is a good (albeit more arcane) way to search for these parts. 

Picking a Machine Shop

In reality, your best bet to get the most faithful representation of your truck's original hydraulic system is to go to a machine shop to have the part made uniquely. A machine shop will be able to make the part precisely for your project, no matter how much of the hydraulic system you need made. Often the part of the system that fails soonest is the hydraulic cylinder, as this is the heart of the hydraulic system itself. It is for this reason that it is best to go through a dedicated hydraulic repair machine shop so that the team on staff will be able to handle the entire project, as opposed to having a different shop handle the hydraulic cylinder from the one handling the rest of the parts. 

Copying the Part

The custom approach is particularly useful if you can bring the actual derelict part to the shop so that they can create a workable model of what the part looked like the day it was made. Also, this approach will allow you to have the part made from similar looking materials to the original, if not the exact same materials. This is important to maintaining the original look of the part so that it blends in seamlessly with the rest of the restored vehicle. 

Contact a service like Certified Products Co for more help.