Suspension and steering decide how a truck rides, how it handles a load and how fast it eats tires. On a diesel pickup towing a camper, a tractor running at 80,000 pounds gross or a motorhome on air ride, worn parts show up as sway, wander and uneven wear long before anything breaks. RDI Power repairs shocks, suspension and steering at our Brooksville shop.
Shocks, springs and steering: what each does
- Springs carry the weight: leaf springs on most pickup rear axles and many heavy trucks, coil springs on some front ends, and air springs on air-ride tractors, trailers, buses and motorhomes.
- Shocks control how fast the springs move. Worn shocks let the truck bounce, dive and roll, and let tires skip over bumps.
- Steering and linkage keep the wheels pointed where the driver wants: steering gear, pitman and idler arms, tie rods, drag links, ball joints, and on heavy trucks, kingpins.
Symptoms that send trucks our way
- Bouncing or floating after dips and bridge joints
- Sway or a pushing feeling when towing
- Nose dive under braking
- A sagging corner, or uneven ride height
- Wander, loose steering or a steering wheel that is off center
- Clunks or rattles over bumps
- Cupped or scalloped tire wear
- On solid-axle pickups, a violent front-end shake after hitting a bump at speed
Suspension inspection
We road test first, then put the truck on the lift. Shocks get checked for leaks, damage and worn mounts. Springs get checked for broken leaves, worn bushings and shackles, and sag. Steering components get a dry park check, with someone turning the wheel while we watch every joint for play. On air-ride suspensions, we look for leaking air springs and lines and check height control valve adjustment. Ride height gets measured against spec.
Heavy trucks and air ride
Air-ride tractors depend on height control valves to keep the suspension at the right height. A valve out of adjustment changes driveline angles and fifth wheel height and can cause vibration. Torque rods and their bushings keep the axles aligned; when they wear, the truck can dog-track. Kingpins wear on steer axles and show up as wander and steer tire wear. These are also items a DOT inspection looks at.
Pickups and towing
Diesel pickups often carry more than their springs were tuned for, with fifth wheel and gooseneck trailers, service bodies or plows. Shocks wear faster under that load, and front-end parts take the weight of a heavy diesel engine over every bump. If the truck tows regularly, the hitch and suspension should be inspected together.
Motorhomes and buses
Diesel pusher RVs and buses ride on air suspensions with shocks, leveling valves and air springs. A coach that leans, sways in crosswinds or rides rough often needs shocks or valve adjustment. See RV service and repair.
Suspension and steering repairs
- Shocks replaced in pairs, matched to the vehicle and its load
- Leaf springs, spring bushings, shackles and hangers
- Air springs, height control valves and air lines
- Steering gear, tie rods, drag links, pitman and idler arms, ball joints and kingpins
- Torque rods and suspension bushings
- An alignment afterward on our truck alignment equipment, and a look at tire wear so the cause and the damage both get addressed
If your truck bounces, wanders or is wearing tires unevenly, bring it in for a suspension and steering inspection.