Monroe RV Gas-Magnum Shock Absorbers
Monroe RV Gas-Magnum includes two series by primary motorhome use and dimensions: 555xx for many Class B/C and tow-vehicle applications, and 557xx primarily for Class A applications. Those groupings help explain the range, but coach class alone is not enough to select an exact shock.
Gas-Magnum series comparison
| Reference specification | 555xx series | 557xx series |
|---|---|---|
| Typical use | Class B/C and tow vehicles | Class A, front- and rear-engine |
| Bore | 1⅜ inches | 1¾ inches |
| Reserve tube | 2 inches | 2.38 inches |
| Piston-rod seal | Multilip | Single lip |
| Gas charging | Nitrogen charged | Low-pressure nitrogen; 60 psi reference specification |
Use the exact chassis and axle-position listing to select a shock. Series dimensions help compare designs but do not identify the correct application on their own.
Match the chassis and axle position
A motorhome’s body manufacturer may differ from the chassis manufacturer. Record the chassis type and year, then confirm front/rear position, mounting configuration and relevant suspension options. Do not choose a 555xx or 557xx part solely because your coach is Class C or Class A.
A front-engine and a rear-engine coach can have different requirements despite sharing a broad class label. The actual part listing must support the chassis and position.
Damping versus support
Gas-Magnum shocks are gas-charged dampers. Their role is controlling suspension motion; they do not raise the motorhome’s weight ratings or replace springs. Continuing sway, sag or wandering may call for additional diagnosis rather than another damper selection.
Inspect mounts, bushings, springs, tires and load distribution. Bore size alone does not determine ride quality or suitability for a different coach.
Prepare a replacement inquiry
- Supply chassis make, model or series and model year.
- Identify front/rear position and existing part numbers when available.
- Disclose suspension modifications and unusual mounting arrangements.
- Confirm quantities, bushings and included hardware.
Use a qualified installer and the correct torque and mounting procedures. If a listing conflicts with your chassis details, resolve that before ordering.
Frequently asked questions
Can I choose RV shocks using Class A, B or C alone?
No. Exact chassis, axle position and application details are required.
How do the Gas-Magnum series bore sizes compare?
It lists 1⅜ inches for 555xx and 1¾ inches for 557xx. Confirm the actual product’s specifications before selection.
Do RV Gas-Magnum shocks increase load capacity?
No. Dampers control movement and do not change the vehicle’s original weight ratings or replace its springs.
