The truck's frame features stronger single-channel steel rails rated at 50,000, 80,000 and 120,000-lb. per sq. in. to reduce the need for rail inserts for many applications. With less need for rail inserts, the frame is lighter overall, so operators can haul more payload.
The front suspension incorporates single-leaf springs as standard equipment. Taper-leaf suspensions are available in a range of capacities from 8,000 to 18,000-lb., with maintenance-free rubber bushings. Flat-leaf springs are also available rated at 14,600, 16,000 and 18,000-lb. capacities. Maintenance-free front spring bushings are standard.
For 4x2 applications, a replaceable spring deflection pad is used instead of a shackle on the rear of each front spring. The 12,000-lb. front suspension option is supplied with the single-leaf spring with a rear spring shackle, plus rubber spring bushings on both ends, for longer life and improved ride.
The suspension's rear shackles are spring-mounted, contributing to a smooth and quiet ride, and a slipper pad is standard. The improvements to the Acterra's rear suspension enhance the truck's ride, and the suspension is now lubrication-free.
Two suspension packages are available. The 52-inch variable rate taper leaf rear suspension is standard in a six-step range of capacities rated from 18,000 to 23,000 lbs. Shock absorbers can be added to improve the ride, and an optional low maintenance rubber helper pad provides extra load support and stability. An optional rear stabilizer bar improves handling.
The optional 60-inch two-stage spring rear suspension package comes in 18,000-, 21,000- and 23,000-lb. ratings. Sterling said this design offers the best option for quiet and sure handling over demanding road surfaces without the added cost of an air suspension. Anti-friction spacers are standard, along with shock absorbers, rear shackle mounts and the rubber helper.
Optional 60-inch air rear suspensions are available in ratings from 10,000 to 40,000 lb., plus extra-duty ratings of 40,000 and 46,000-lb. capacities. A stabilizer bar is available for both the spring and air suspensions.
For vocational applications, customers also can spec the Freightliner TufTrac suspension rated from 40,000 to 46,000-lb. capacity. Hendrickson rear suspensions are available with 40,000 or 46,000-lb. in the RT/RTE or HN series. Hendrickson's RS series suspension is another option, rated at 52,000-lb.
In addition to the component enhancements, Sterling engineers made a number of design changes to facilitate body and equipment installation as well as to ease maintenance.
One option improves body installation by reducing back-of-cab component installation. A new battery box/air tank/air dryer package places the components out of the way where they can't interfere with body installations. The installation includes the steel and plastic battery box, dual 9-in. air tanks and the Bendix DRM AD-IS air dryer system. The standard Bendix AD-9 air dryer is mounted on the front of the chassis, where it is protected from road debris by the bumper.
Air lines are mounted on the driver's side of the frame, minimizing the number of lines that must cross the frame. The line placement gives a clean appearance to the frame and reduces the risk of snagging critical lines during body installation.
New lightweight rectangular aluminum fuel tanks are standard for maximum ground clearance and easier body installation. Their aluminum construction helps reduce corrosion inside the tank. To ease body installations, clean back-of-cab configurations are available with 30-, 40- and 50-gal. fuel tanks. Tanks range in size from 30 to 100 gal.
Maintenance of the new Sterling Acterra is made even easier thanks to a new see-through power steering fluid reservoir that lets operators check levels quickly during their inspection routines.
According to Sterling, the Acterra can be customized to meet the needs of nearly any application and can be spec'ed with Mercedes-Benz, Caterpillar and Cummins diesel engines.
