SHOCKS

Shocks For Peterbilt Trucks

Shock absorbers control the oscillation of the suspension after road impacts — without them, a Peterbilt would bounce continuously on its springs, making the truck difficult to control and causing rapid tire wear from irregular road contact. On steer axles especially, worn shocks contribute to shimmy, wander, and driver fatigue on long runs. We carry replacement shock absorbers for Peterbilt trucks in standard and heavy-duty valving for steer, drive, and tag axle applications.

Frequently asked questions about shocks

How do I know when shock absorbers need to be replaced on a Peterbilt?

The most common signs of worn shocks are excessive cab bounce after hitting a bump, steering shimmy or wheel hop at highway speeds, and cupped or scalloped tire wear patterns that develop from the tire losing consistent road contact. A physical inspection of the shock body for oil leakage — wet streaking down the shock body — confirms the shock seal has failed and the unit should be replaced. Shocks should also be inspected for bent bodies, damaged mounts, and worn bushings at each PM service.

Should shocks be replaced in pairs on a Peterbilt?

Yes — always replace shocks in axle pairs. A new shock on one side of an axle and a worn shock on the other creates uneven damping that causes the truck to respond differently to road inputs on each side, contributing to handling pull and uneven tire wear. On the steer axle especially, mismatched shocks make steering feel unpredictable and can mask other front-end issues. The modest additional cost of replacing both units is always worthwhile.

What's the difference between standard and heavy-duty shocks for a Peterbilt?

Standard valving shocks are calibrated for normal highway operation at typical loads. Heavy-duty or severe-service shocks use stiffer valving and more robust internal construction to handle the higher suspension velocities and loads seen in vocational applications — construction, logging, oil field, or any operation involving rough roads and high gross weights. Running heavy-duty shocks on a highway truck can make the ride excessively stiff; running standard shocks on a vocational truck results in rapid shock failure from overworking the damping fluid and seals.

Other parts you might need

Shop suspension, steering & axles for Peterbilt trucks