Technical Info

Trailer Hardware Service Information

10 Ton Air Suspension Fabricated & Parabolic Type Torque Requirements

Check torque values after 'Break In' period of approximately 1000 to 3000 miles (1600 to 4800Km) and annually thereafter.

Quick-Align pivot bolt connection fabricated type 505-595 ft-lb (685-807Nm)
Quick-Align pivot bolt connection parabolic type 406-443 ft-lb (550-600Nm)
Shock Absorber Bolts 295-310 ft-lb (400-420Nm)
U-Bolt Nuts 443-480 ft-lb (600-650Nm)
Upper Air Spring Nuts 44-52 ft-lb (60-70Nm)
Lower Air Spring Nuts 88-96 ft-lb (120-130Nm)
Brake Chamber Mounting Nuts 100-110 ft-lb (136-149Nm)
S-Cam Support Bearing Mounting Nut 35-45 ft-lb (47-61Nm)
Check Condition of Airbags Weekly    
Check Trailing Arms for stress cracks Monthly    

5 Ton Air Suspension Parabolic Type Torque Requirements

Check torque values after 'Break In'period of approximately 1000 to 3000 miles (1600 to 4800Km) and annually thereafter.

Quick-Align pivot bolt (M24x3P, 8.8) 442 ft-lb (600Nm)
Shock Absorber Bolts (M14x2P, 8.8) 84 ft-lb (115Nm)
U-Bolt Nuts (5/8"UNF, Grade 8) 120 ft-lb (163Nm)
Upper Air Spring Nuts (3/4"UNC, Grade 5) 100 ft-lb (135Nm)
Lower Air Spring Nuts (3/8"UNC, Grade 5) 26 ft-lb (35Nm)
Lower Air Sping Bracket Bolt (M10x1.5P, 10.9) 48 ft-lb (65Nm)
Brake Chamber Mounting Nut 100-110 ft-lb (136-149Nm)
S-Cam Support Bearing Mounting Nut 35-45 ft-lb (47-61Nm)
Check Condition of Airbags Weekly    
Check Trailing Arms for stress cracks Monthly    

3 Ton Air Suspension Parabolic Type Torque Requirements

Check torque values after 'Break In'period of approximately 1000 to 3000 miles (1600 to 4800Km) and annually thereafter.

Quick-Align pivot bolt (M24x3P, 8.8) 442 ft-lb (600Nm)
Shock Absorber Bolts (M14x2P, 8.8) 84 ft-lb (115Nm)
U-Bolt Nuts (5/8"UNF, Grade 8) 120 ft-lb (163Nm)
Upper Air Spring Nuts (3/4"UNC, Grade 5) 26 ft-lb (35Nm)
Lower Air Spring Nuts (3/8"UNC, Grade 5) 26 ft-lb (35Nm)
Lower Air Sping Bracket Bolt (M10x1.5P, 10.9) 48 ft-lb (65Nm)
Brake Chamber Mounting Nut 100-110 ft-lb (136-149Nm)
S-Cam Support Bearing Mounting Nut 35-45 ft-lb (47-61Nm)
Check Condition of Airbags Weekly    
Check Trailing Arms for stress cracks Monthly    

10 Ton Mechanical Suspension and Axle Torque Requirements

Check torque values after 'Break In'period of approximately 1000 to 3000 miles (1600 to 4800Km) and annually thereafter.

U-Bolt Nuts 368-398 ft-lb (500-540Nm)
Torque Arm Nuts, 1" 406-443 ft-lb (190-220Nm)
Adjustable Torque Arm Clamp Nuts, 5/8" 295-310 ft-lb (170-205Nm)
Equalizer Bolt, 1" 443-480 ft-lb (545-610Nm)
Retainer Bolt Nuts, 1/2" 44-52 ft-lb (95-110Nm)
Check Wheel Nuts Torque Settings 88-96 ft-lb (610-678Nm)
Check Outer Axle Nut Torque 100-110 ft-lb (427-521Nm)
Check Grease Cap for Tension    
Check Bearing Grease every 12 Months    

5 Ton Mechanical Suspension and Axle Torque Requirements

Check torque values after 'Break In'period of approximately 1000 to 3000 miles (1600 to 4800Km) and annually thereafter.

U-Bolt Nuts (5/8" UNF, Grade 8) 120 ft-lb (163Nm)
Leaf Spring Eye Bolt (M20x2.5P, 8.8) 265 ft-lb (360Nm)
Rocker Hanger Bolt (M30x3.5P, 8.8) 885 ft-lb (1200Nm)
Rear Hanger Bolt Nuts (M16x2P, 8.8) 7.5 ft-lb (10Nm)
Check Wheel Nuts Torque Settings 450-500 ft-lb (610-678Nm)
Check Outer Axle Nut Torque 315-385 ft-lb (427-521Nm)
Check Grease Cap for Tension    
Check Bearing Grease every 12 Months    

3 Ton MechanicalSuspension and Axle Torque Requirements

Check torque values after 'Break In'period of approximately 1000 to 3000 miles (1600 to 4800Km) and annually thereafter.

U-Bolt Nuts (5/8"UNF, Grade 8) 120 ft-lb (163Nm)
Leaf Spring Eye Bolt (M20x2.5P, 8.8)  265 ft-lb (360Nm)
Rocker Hanger Bolt (M24x3.5P, 8.8) 442 ft-lb (600Nm)
Rear Hanger Bolt Nuts (M16x2P, 8.8) 7.5 ft-lb (10Nm)
Check Wheel Nuts Torque Settings 90 ft-lb (122Nm)
Check Outer Axle Nut Torque 315-385 ft-lb (427-521Nm)
Check Grease Cap for Tension    
Check Bearing Grease every 12 Months    

Note: The above settings must be maintained at all times. Values are expressed in English units, ft-lb = foot-pounds & Metric units, Nm = Newton-Meters


Axle Torque Requirements

Check torque values after 'Break In'period of approximately 1000 to 3000 miles (1600 to 4800Km) and annually thereafter.

  • 10 Ton Axles (10 x 225 PCD, 8 x 275 PDC, 10 x 335 PCD)
    M22 x 1.5P (10.9) - 400-500 ft-lb (610-678 Nm)
     
  • 10 Ton Axles (20" 6 Spoke Spider, 15" 3 Spoke Spider)
    3/4" UNC Gr.8 - 200-220 ft-lb (270-300 Nm)
     
  • 5 Ton Axles (Both Bud Nut & Flange Nut Pattern)
    M20 x 1.5P (10.9) - 332 ft-lb (450 Nm)
     
  • 3 Ton Axles (Both Electric and S-Cam Style)
    1/2" UNF Gr.8 - 120 ft-lb (162 Nm)

Maintenance Schedule Downloads


Technical Terms

ATM and GTM
The maximum weight of a trailer is specified as either its Aggregate Trailer Mass (ATM) or Gross Trailer Mass (GTM).

ATM is the combined weight of the trailer and its full load when it is not coupled to a tow vehicle. GTM is the weight of the fully loaded trailer that is imposed o the trailers axle when it is coupled to the tow vehicle. GTM will always be less than ATM as some of the trailer weight is transferred to the tow vehicle when the trailer is coupled to it.

All new vehicles built since August 1989 are required to have a plate listing, amongst other things, the trailers Aggregate Trailer Mass, although some trailer plates will also show its Tare weight (the unladen weight of the trailer) and its GTM.
You must ensure the towing vehicle has sufficient capacity to tow the trailer when it is fully laden.

GCVM
Gross Combination Vehicle Mass (where given) is the maximum allowable weight of the trailer, tow vehicle and the load in the tow vehicle and trailer (including passengers).


Road Train Combinations

Road Train Combinations