Know The Difference

 

Know the Difference Between Normal and Abnormal Functioning of Your Vehicle

Normal noises

• A hissing noise happens every time the steering wheel turns.
• A fluid noise happens during every full turn.
• A noise occurs every time the system relief valve operates.
• Some types of steering pumps emit a pump 'growl'.

Abnormal Noises

• Loose Belts. Belt-driven steering pumps give off squealing nose. Tighten belts.
• A clicking noise sounds during turns or change of direction. Some part may be loose and need to be tightened or replaced.
• There is a change in the 'normal' noise of the steering pump.
• Air may have entered the system or fluid is low.
• Valve may be faulty or pump is wearing out.
• Hoses may be kinked or plugged.
• Filter may be plugged.

Drift or Wander

• Incorrect or unequal tire pressure - side to side.
• Steering wheel to road wheel linkage components may be loose or worn.
• Wheel bearings may be improperly adjusted or worn.
• Front end needs realignment.
• Rear end needs realignment.
• Fifth wheel or trailer plate may be dry or have a poor finish.
• Steering gear mounting bolts may be loose on frame.
• Pitman arm is loose on the sector shaft.
• Steering gear may be improperly adjusted or worn out.
• Loose rear axle assemblies or trailer bogies.
• Radial tires on vehicle designed to use biased ply tires. (1972 - earlier)
• Brakes are dragging.
• Frame is bent.
• Shocks or springs are faulty.

No Recovery

• Tire pressure is low.
• Front end components are binding. (Must be checked with weight on front end)
• Front end alignment is incorrect.
• Kingpins on front axle are tight. (Must be checked with weight on front end)
• Fifth wheel or trailer plate may be dry or have a poor finish
• Steering column is binding
• Steering pump has insufficient flow.
• Steering gear is improperly adjusted.

Shimmy

• Tires are unevenly or badly worn.
• Tires or wheels are improperly mounted.
• Wheel bearings are improperly adjusted or worn.
• Steering linkage components are loose or worn.
• Wheels or brake drums are out of balance.
• Front end alignment is incorrect.
• Hydraulic system has air in it.
• Steering gear has 'free' play.
• Gearbox may be improperly adjusted.

External Oil Leaks

• Check all fittings, hoses, pump or gear. (Leak location may be difficult to find because oil may flow away from source to lowest point.)
• Vent plug leak at side cover - failure of sector shaft oil seal inside side cover.

Darting or Oversteering

• Fifth wheel or trailer plate may be dry or have a poor finish.
• Front end components are binding or loose.
• Steering column is binding.
• Steering gear is improperly adjusted.
• Steering gear control valve sleeve is sticking.
• Rear axle mounts may be faulty. (Rear steer)

Increased Steering Effort in One Direction

• Tire pressure is unequal.
• Vehicle is overloaded.
• Hydraulic system has inadequate pressure.
• Gear Box has excessive internal leakage in direction of turn.
• Steering gear valve is not properly adjusted.
• Control valve is not properly adjusted.

Increased Steering Effort in Both Directions

• Tire pressure is low.
• Vehicle is overloaded.
• Hydraulic fluid level is low.
• Hydraulic fluid is incorrect type.
• Steering pump has low pressure or flow.
• Steering system components are binding.
• Return line has some restriction or too small a diameter.
• Tires are oversized. (Check against manufacturer's specifications.)
• Steering pump drive belt is loose.

Excessive Heat (150°F/65.5°C)

• Steering pump has excessive flow.
• Vehicle is overloaded.
• Replacement hose or line is undersized.
• Hose or line restricted - kink, severe bend, internal blockage.
• Restricted re-centering of gear - caused by column bind or side load on input shaft.
• Poppets are not adjusted properly
• Vehicle operated in stationary position for prolonged periods of time.
• Steering system components are binding.
• Return line has some restriction or too small a diameter.
• There is excessive internal leakage.
• Tires are oversized. (Check against manufacturer's specifications.)
• Steering pump drive belt is loose.
• Front end needs lubrication.
• Front end is improperly aligned.
• There is air in hydraulic system.

Excessive Play at the Steering Wheel

• Steering wheel is loose on the shaft.
• A loose connection exists between steering gear, intermediate column, and steering column.
• Steering gear is loose on the frame.
• Pitman arm is loose on the sector shaft.
• Steering linkage components are loose or worn.
• Steering gear is improperly adjusted or defective.
• Steering pump has low pressure.

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