FIREMAAX® EX for Fire/Rescue

Heavy-duty rear air suspension for fire and rescue applications

FIREMAAX EX Heavy-duty Rear Air Suspension for Fire Trucks

FIREMAAX® EX heavy-duty rear air suspension delivers the superb ride, stability, and handling required for fire and rescue vehicles. Combining a robust design with performance enhancing features, FIREMAAX EX provides a package of benefits previously unavailable in any one emergency vehicle air suspension.

FIREMAAX EX Heavy-duty Rear Air Suspension for Fire Trucks

Features and Benefits

  • Capacity ratings tested for fire and rescue applications
  • Improved ride for equipment, vehicle and passenger protection
  • Exceptional handling for greater control during road maneuvers
  • Dual height control valves for weight biased vehicles
  • Integrated stabilizer design results in greater stability
  • Up to 12.5 inches of diagonal wheel articulation for improved mobility
  • Heavy-duty shock absorbers to protect air springs from overextension
  • Premium, heavy-duty rubber bushings require no lubrication
  • QUIK-ALIGN® system simplifies axle alignment
  • Heavy-duty torque rods and bushings are performance tested for longer service life
  • Air springs and shock absorbers designed to package within tire envelope for protection from external damage
  • Higher gross weight ratings with greater versatility


Model FMX 242 FMX 272 FMX 312 FMX 482 FMX 542 FMX 622
Capacity (lbs.) 24,000 27,000 31,000 48,000 54,000 62,000
Installed Weight1 (lbs.) 550 658 665 1,090 1,305 1320
Axle Configuration Single Single Single Tandem Tandem Tandem
Axle Travel2 (in.) 8 8 8 8 8 8
Ground Clearance3 (in.) 10.75 10.5 10.5 10.75 10.5 10.5
Ride Heights4 (in.) 8.5 to 15.5 8.5 to 12.5 8.5,10,13 8.5 to 15.5 8.5 to 12.5 8.5,10,13
Axle Spacing (in.) N/A N/A N/A 52 to 72.5 54 to 72.5 54 to 72.5
Disk Brake Compatibility Yes Yes No Yes Yes No
  • FIREMAAX® EX capacity ratings apply to fire and rescue market only
  • FIREMAAX EX may be referred to as PRIMAAX® EX by some OEMs
  • Refer to Hendrickson's technical literature for complete operating details
  • All applications must comply with applicable Hendrickson specifications and must also be approved by the respective vehicle manufacturer with the vehicle in its original, as-built configuration. Contact Hendrickson and the respective vehicle manufacturer for approval of additional applications
  • For additional details regarding specifications, applications, capacities, operating, service and maintenance instructions, refer to applicable Hendrickson technical literature or contact Hendrickson at 630-910-2800

1. Installed weight includes complete suspension, torque rods, axle and frame brackets and all hardware. Published weight is based on a standard FIREMAAX EX suspension compatible with drum brakes using 10.0-inch ride height. Other configurations may vary.

2. Axle travel may be limited by vehicle manufacturer; axle stop settings and shock stroke may restrict suspension's articulation. Varying ride heights and configurations may restrict travel.

3. Ground clearance is based on a standard FIREMAAX EX suspension with 11R22.5 tire size.

4. For different ride height options, please contact Hendrickson (630-910-2800), your truck manufacturer or your dealer.


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