Here is the Donval Information:
First the intro letter
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Enclosed is information on the Donvel Active Ride Control and Stabilizing System. This is a
unique air ride system for which Donvel has received two patents. There is nothing else like the
Donvel Stabilizers on the market, because these units are controlling constantly and take away bounce, dip, snap and sway.
Each set is built for the truck it goes on. They are shipped assembled and have the normal
control needed built into them to give quickness of response to each bump. However, should the customer desire a softer ride, or a quicker, finer ride, we can change the control and give them anything they need. The driver adjusts the pressure needed for each load balance, fifth-wheel setting, and trailer axle setting. We build internally how fast the units are reacting to the pressure the driver gives them. The holding and releasing effect automatically flattens the steer axle's response to bumps, bad bridges, wind sway, body roll and road walk.
Most trucks have fine front springs, but steel springs by nature react to impacts in a certain way that can be very harsh (dips, bridges, pot holes, etc.). Donvel addresses this point of impact at the source (the steer axle) with air stabilizers designed to react very quickly to the spring when it compresses and snaps back. This reduces the workload that shock absorbers are subjected to. This improvement reduces back slap, steering wheel shake, and wear and tear on the cab and sensitive electronic accessories, not to mention the most important component, the driver.
There are many fine products on the market striving to improve the ride farther back on the truck. Why not make their job easier by solving much of the problem at the source with driver- controlled Donvel Ride Control Stabilizers? Because some older models of trucks may have had suspension changes, we are enclosing a measurement sheet which enables us to build a custom unit for such trucks. If this applies in your case, please fax or mail us this sheet any time at your convenience.
If sleeper rock and bounce is a problem, take a look at the unique new cab and sleeper controls by Donvel. Once installed in the air lines close to the air springs on the sleeper, they take all the excess sleeper roll and bounce away and never wear out or need replacing. This control is also available for
drive axles and seats. Thanks again for your interest, and feel free to call me if you have any questions.
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PROBLEM
When a truck hits a bridge or cross rib, the steel springs load up with energy and then immediately snap back with considerable force.
This load up action is made worse when the fifth wheel is slid forward and additional forces come into play. First, there is the increased weight on the steer axle as well as the forward inertia of the entire vehicle. These combine in a leverage effect to force further load on the steer axle when a bridge or pothole is hit.
SOLUTION
Donvel driver-adjustable air stabilizers are installed in the right location to give the best possible control of excess spring and body movement. When a bump or bridge is hit, the resulting forces are controlled and greatly reduced, so that shock absorbers have less work to do.
PROBLEM
A nose heavy trailer bouncing on the fifth wheel, making the front end leap and bounce.
SOLUTION
Carry more of the front end weight with Donvel stabilizers by increasing the air pressure to 45 - 65 p.s.i. This will give a more stable ride with less bounce.
When trucks hit cross ribs, bridge ramps and potholes, etc., extreme forces are transferred to the steering axle. The load balance, trailer axle settings and fifth wheel settings have a profound effect on how these forces are directed to the steering axle.
