Prev Next Freightliner — Tuftrac Description 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. LP46-24808 – upper pad, 40k suspension LP46-24581 – upper pad, 46k suspension LP46-24807 – lower pad, used on both 40k & 46k suspension 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 Upper End Pad LP46-24808 LP46-24581 All Products Lower End Pad LP46-24807 All Products Lower Torque Rod TR46-49002 TR46-49004 TR46-49998 All Products Torque Rod Bushing TS46-22300 All Products Details Freighliner Tuftrac Load cusion, spring, lower torque rods. Prev Next