Freightliner — Tuftrac | ATRO Engineered Systems, Inc.

Freightliner — Tuftrac

Freightliner — Tuftrac


This vocational suspension combines parabolic springs with elastomeric load cushions. The center elastomer load cushion acts as a pivot point to allow articulation while smoothing out the typically harsher ride experienced with spring-only suspensions. The end spring pads cushion the ride, especially unladen, and reduce noise and vibration. This suspension design also raises the undercarriage components for more ground clearance.

Vocational uses include refuse, construction, asphalt spreader, heavy hauling, mining, logging, oil/gas field service and high-center-of-gravity applications; 40k, 46k and 52k capacities.

The OE offers two options for the 40k and 46k models: TufTrac and 2-Stage Tuftrac. The 2-Stage version uses a center bearing with a softer spring rate due to voids in the rubber material between the steel plates.

 Tech Tips and Additional Resources

ATRO offers the upper and lower spring end pads, lower torque rods and torque rods bushings:

  • Upper and lower spring end pads – ATRO’s load spring with proprietary poly specifically formulated to resist compression set while absorbing shock and dampening vibration rather than transferring it into the spring or frame.
  • Lower torque rods – The OE uses two different rods in the front and rear locations that are identical except for the bushing orientation within the rod.
  • Torque rod bushings – eliminates part numbers with a 360° rotation of the inner pin.
    • TR46-49002 – used on 40k suspension with 54” axle spacing
    • TR46-49004 – used on 46-52k suspension with 60” axle spacing
    • TR46-49998 – used on 46-52k suspension with 56” axle spacing
    • These ATRO rods above do not accept the OE snap ring-style bushing.
  • Torque rod bushing for rebushing any of the lower rods
    • TS46-22300 - fits all lower ATRO rods- does not fit OE rods.
    • Has rotating pins for easy installation and elimination of torsional stress

 Wear Items

  • End load pads
  • Lower torque rod/bushings

 Key Parts


Freightliner Tuftrac suspension details
Freighliner Tuftrac

Load cusion, spring, lower torque rods.