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Hydraulic Steering Tech - Hydraulic Steering 101

Steering Ram Closeup
Robin Stover | Writer
Posted November 1, 2006
Photographers: Edwin Sargenti

Full hydraulic vs. hydro-assist

Hydraulic steering can make or break a trail machine. An inadequate system can over-exercise arm muscles while making tight maneuvers very frustrating. Or, if well designed, a hydraulic steering system can actually contribute to the overall enjoyment of a day in the dirt. That's because the amount of physical effort it takes the driver to turn the steering wheel relates directly to how well the hydraulic system functions. A poorly designed system or even a simple misuse of parts for a particular application can result in sluggish, hard-to-use steering - not to mention the ill effect on reliability. That's why we decided to delve into the subject of hydraulics and address a few common issues, while at the same time contrasting the two popular types of setups we see on the trail. We're going to break this somewhat complex topic into two categories.

This is a typical full hydraulic steering system.

Full Hydro
Traditionally, this has always been the point where most 'wheelers cross the line between a trail-only rig and a daily driver. This is because most people feel hydraulic systems are unreliable and therefore not suitable for the street. However, this is not necessarily true. Take a look at the heavy equipment industry: Caterpillar tractors, for example, rely on a variety of hydraulic systems to function, many of which control directional movement. Hydraulic steering systems have their place in several street-driving scenarios, too, though most are found on industrial or agricultural equipment operated at low speeds. These systems are engineered to perform a specific task within a specific range of parameters (i.e., speed, weight, temperature, and environment). The problem here - and probably part of the reason why fully hydraulic steering gets a bad rap on the street - is due to system design, or lack thereof. It all boils down to economics. No common man is willing to invest the millions it took Caterpillar to develop a fully hydraulic steering system reliable enough to pilot its dump trucks down the road safely. And because there are several sources for hydraulic steering components, all with very little "specific information" about each particular application, it's hard for Joe Consumer to know which widget to install on his own rig. Full hydraulic steering requires eight major components: Each is equally important to the overall performance of the system. That's why it's most important to build a balanced or matched system.

Ram Assist
For most 'wheelers, the somewhat less expensive, less complex hydraulic assist may be the best option. In most cases, companies offer complete kits for specific vehicle applications like the PSC kit shown above for the '05 Jeep TJ. With an assist setup, your rig's mechanical steering remains intact, enabling the option of manual steering if the hydraulics should fail. We like this setup for trail rigs that are driven on pavement from time to time. Aside from helping your steering system push around larger meats, a ram assist can function as the ultimate steering dampener, too. At the same time, a ram assist also helps relieve stress on other steering components such as the steering box. The major difference between hydro-assist and fully hydraulic steering is that hydro-assist is basically a piggyback setup you add on to your existing steering system, while a fully hydraulic system is a stand-alone system relying completely on fluid power.


Howe Performance
Lakeside, CA 92040
Performance Off-Road Systems
PSC Motor Sports
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