Heavy-duty Air Suspension


With its rugged, weight efficient design, PRIMAAX® EX is a severe-duty vocational air suspension that delivers advanced suspension technology for the rigorous demands of vocational, severe-service, and heavy-haul applications. The system features a robust structural design with optimized suspension geometry for exceptional stability, handling and ride. Suspension-induced driveline vibration is significantly reduced with PRIMAAX EX compared to competitive trailing-arm air suspensions, resulting in higher driver comfort and less premature wear on expensive truck and body equipment.


Model PAX 232 PAX 262 PAX 462 PAX 522 PAX 692 PAX 782
Capacity (lbs.) 23,000 26,000 46,000 52,000 69,000 78,000
Installed Weight1 (lbs.) 542 651 1,078 1,292 1,629 1,931
Axle Configuration Single Single Tandem Tandem Tridem Tridem
GCW Approval2 (lbs.) 90,000 140,000 190,000 245,000 See 6 See 6
Site Travel Rating3 (lbs.) 30,000 33,000 60,000 66,000 90,000 99,000
Axle Travel4 (in.) 8 8 8 8 8 8
Ground Clearance (in.) 10.75 10.5 10.75 10.5 10.75 10.5
Lift Axles Approved Approved Approved Approved Approved Approved
Ride Heights5 (in.) 8.5 to 10.5
12.5 to 15.5
8.5 to 10.5
12.5 to 15.5
8.5 to 10.5
12.5 to 15.5
8.5 to 10.5
12.5 to 15.5
8.5 to 10.5
12.5 to 15.5
8.5 to 10.5
12.5 to 15.5
Engine Torque Restrictions None None None None None None
Axle Spacing (in.) N/A N/A 52 to 72.5 54 to 72.5 52 to 60 54 to 60

1. Installed weight includes complete suspension, torque rods, axle and frame brackets and all hardware. Published weight is for standard PRIMAAX EX suspension using 10.0-inch ride height. Other configurations may change weight.

2. Contact Hendrickson or original equipment manufacturer for applications that may exceed GVW / GCW approval ratings.

3. Site Travel Rating — Operators using vehicles equipped with liftable push or tag axles must not exceed published ratings. Ratings are limited to no more than five percent of vehicle operation at a speed not to exceed five mph. Liftable pusher or tax axles should be raised (or unloaded) to improve vehicle maneuverability in severe-duty use or when vehicle is empty. Site travel ratings are consistent with specifications and must not be exceeded.

4. 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.

5. For different ride height options, please contact Hendrickson, your truck manufacturer or dealer for further information.

6. Refer to axle manufacturer's recommendation.

Features & Benefits


About Us

Hendrickson Defense is a leading manufacturer and supplier of premium defense suspension components to global markets.

Our legacy embodies over 80 years as the leading innovator and manufacturer of suspension systems and components for the global heavy-duty vehicle industry.

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Hendrickson Defense
800 South Frontage Road
Woodridge, IL 60517