POSSIBLE STEERING PROBLEMS AND CAUSES
NORMAL NOISES
- You or the driver may hear a hissing noise from the control valve when it is actuated during a steering maneuver.
- You or the driver may hear a noise as fluid bypasses through the poppets at full turn.
- You or the driver may hear a noise from the system relief valve when it is required to actuate.
- You or the driver may hear pump growl from some types of power steering pumps
ABNORMAL NOISES
- If the power steering pump is belt-driven, a squealing noise may indicate that the belts should be tightened or replaced.
- A clicking noise heard during a turn, or when changing directions, may indicate that some component is loose and shifting under load.
- A change in the normal noise of the pump may indicate a faulty valve or wear in the pump.
- A change in the normal noise of the pump may be due to kinked or plugged hoses.
- Because of the plugged filter, there may be whining from the pump.
- Improper adjustment of the gearbox will result in abnormal noise from the pump.
ROAD WANDER
- Tire pressure incorrect or unequal left to right.
- Components in steering linkage loose or worn (Steering wheel to road wheel).
- Wheel bearings improperly adjusted or worn.
- Front end alignment out of specification.
- Dry fifth wheel or poor finish on the fifth wheel or trailer plate.
- Steering gear mounting bolts loose on the frame.
- Steering gear improperly adjusted.
- Looseness in rear axle assemblies or trailer bogies.
NO RECOVERY
- Tire pressure low
- Front end components binding
- Front end alignment incorrect
- Tight front axle kingpins
- Dry fifth wheel or poor finish on the fifth wheel or trailer plate
- Steering column binding
- Pump flow insufficient
- Steering gear improperly adjusted
- Steering gear control valve sleeve sticking
SHIMMY
- Badly worn or unevenly worn tires
- Improperly mounted tire or wheel
- Wheel bearings improperly adjusted or worn
- Components in steering linkage loose or worn
- Wheels or brake drums out of balance
- Front end alignment incorrect
- The air in the hydraulic system
EXTERNAL OIL LEAKAGE
- Finding the location of a leak may be difficult, since oil may run away from leak source, the fittings, hoses, pumps, or gear to a low point on the gear or chassis.
- A leak from the vent plug at the side cover indicates the failure of the sector shaft oil seal inside the side cover.
OVERSTEERING OR DARTING
- Dry fifth wheel or poor finish on the fifth wheel or trailer plate
- Front end components binding or loose
- Steering column binding
- Steering gear improperly adjusted
- Steering gear control valve sleeve sticking
- Rear-axle mounts (rear steer)
HIGH STEERING EFFORT IN ONE DIRECTION
- Unequal tire pressure
- Vehicle overloaded
- Inadequate hydraulic system pressure
- Excessive internal leakage in one direction of turn only (verify with internal (leakage test)
HIGH STEERING EFFORT IN BOTH DIRECTIONS
- Low tire pressure
- Vehicle overloaded
- Low hydraulic fluid level
- Low pressure or flow from pump
- Components of steering system binding
- Restriction in return line, or line too small in diameter
- Excessive internal leakage (verify with internal leakage test)
- Oversize tires (check manufacturer’s specifications)
LOST MOTION (LASH) AT THE STEERING WHEEL
- Steering wheel loose on the shaft
- Loose connection between the steering gear, intermediate column, and steering column
- Steering gear loose on frame
- Pitman’s arm loose on the output shaft
- Components in steering linkage loose or worn
- Steering gear improperly adjusted
- Worn front spring bushing
EXCESSIVE HEAT (150º F (65.6º C) OVER AMBIENT). NOT TO EXCEED 250º F (121º C) CONTINUOUSLY
- Excessive pump flow
- Vehicle overloaded
- Undersized replacement hose or line
- Restricted hose or line that is kinked or severely bent or internally blocked
- Restricted recentering of gear valve caused by column bind or sideload on the input shaft
- Poppet not adjusted properly (only for gears equipped with poppets)
- Prolonged stationary vehicle operation