Shock Construction
Monroe® Magnum™ shock absorbers are designed to handle the demands of high mileage and severe use, delivering reduced cost-per-mile.
Twin Tube Shock Absorber
The twin tube design has an inner tube known as the pressure tube and an outer tube known as the reserve tube. The outer tube is an oil reservoir. As the rod travels up and down, fluid is pushed / pulled through the base valve and into / out of, the reserve tube. The valving in the piston only operates while submerged in oil. Magnum shocks are engineered with enough oil to fill the reserve tube, regardless of shock travel or position. The pressure tube is always full of oil.
Application Specific Valving
Ride engineers select valve codes or damping force values for a particular vehicle to achieve optimal ride characteristics of balance and stability under a variety of driving conditions. Their selection of bleeds, deflective valve discs, springs and orifices control fluid flow with the unit, which ultimately determines the feel and handling of the vehicle.
Piston Design
Some shock absorbers are constructed using an aluminum die-cast design, requiring a rubber O-ring to prevent oil from bypassing the valve. Monroe Magnum sintered iron piston design allows for more precise piston dimensions, requiring no additional components for improved durability and an exceptional fit.
Piston Design
Robust Hydraulic Lockout
Hydraulic lockout stops, and cushions, the upward movement of the shock, which prevents over extension of the suspension, top-out of the piston and averts damage to the seal assembly. This can help prevent air bags from damaged in extreme situations.
Robust Hydraulic Lockout
Shouldered Bushings
Magnum shock absorbers are engineered with shouldered bushings. The shoulder keeps the bushing located and prevents walkout.
Nitrogen Gas-Charging
Gas-charged shocks add nitrogen to the basic hydraulic shock design to enhance performance and provide a more responsive, smoother ride. Inside a gas-charged shock, a low-pressure charge of nitrogen gas is added in the chamber above the hydraulic oil, helping to reduce fade, minimize vibrations, extend service life and, most importantly, minimize aeration of hydraulic fluid.

Gas charging minimizes hydraulic fluid aeration, which causes foaming. Aeration negatively impacts performance. The addition of nitrogen gas to the shock, compresses air bubbles in the hydraulic fluid and prevents the oil and air from mixing to create foam. By reducing aeration, the gas-charged shock is more responsive and performs better by providing consistent damping.
Consider the Cost of Worn Shocks
Consider the Cost of Worn Shocks
Worn shock absorbers are not only uncomfortable, they can also impact safety, lead to truck downtime and increase operational expense.
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Monroe® Safety Triangle™
Monroe® Safety Triangle™
The Safety Triangle inspection checks critical interconnected system components that control steering, stopping and stability.
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Signs Your Commercial Vehicle Needs New Shocks
Signs Your Commercial Vehicle Needs New Shocks
Service providers follow strict guidelines to determine the condition of commercial vehicle shock absorbers. Shock absorbers should be routinely inspected by a qualified service provider.
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Tire Wear Indicators
Tire Wear Indicators
Understanding the cause of wear pattern can save money on tier costs and preserve safety.
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What Do Shock Absorbers Do?
What Do Shock Absorbers Do?
Commercial vehicle operations may be unaware of gradual shock wear over time. Shocks should be routinely inspected and tested by a service provider as part of scheduled truck maintenance.
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Why Shock Absorbers Wear Out
Why Shock Absorbers Wear Out
Commercial vehicle operators may be unaware of gradual shock wear over time. Shocks should be routinely inspected and tested by a service provider as part of scheduled truck maintenance.
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