Steering Systems Chapter 44
Contents Steering system problem diagnosis Steering system maintenance Steering column service Manual steering gearbox service (recirculating-ball type) Steering linkage service Manual rack-and-pinion service Power steering system service
Steering System Problem Diagnosis Symptoms of steering problems include play in the steering wheel, hard steering, and abnormal noises when turning Inspect and test the steering system to find the source of the trouble
Steering System Problems
Steering Wheel Play Amount that you can turn the steering wheel without front wheel movement Caused by worn ball sockets, a worn idler arm, or too much clearance in the steering gearbox Compare the play to service manual specifications e.g. 1 1/2” (33 mm)
Dry Park Test With the vehicle on the ground, rotate the steering wheel back and forth while someone watches for part wear
Steering Inspection Raise the vehicle on a lift. Wiggle the tires back and forth while watching for steering play
Hard Steering Caused by problems with the steering gear, power steering components, ball sockets, and the suspension system Check the power steering pump belt for condition and tension If the belt is slipping, hard steering could result Check for cracks and glazing and compare tension to specs
Steering System Noise Noise can be a sign of worn parts, dry bearings or ball sockets, loose parts, slipping belts, or low power steering fluid level Belt squeal and power steering pump noise both occur when the steering wheel is turned Pump noise can result from low fluid level or aerated fluid
Steering System Maintenance Maintenance involves checking for low fluid level, incorrect belt adjustment, system leaks, and other problems Ball socket lubrication may be necessary
Check most systems at operating temperature, with the engine off Checking the Fluid Check most systems at operating temperature, with the engine off
Servicing the Belt When changing a belt, pry on a recommended point and adjust tension to specs
Steering Column Service Service is needed after a collision or when internal parts of the column fail Most repairs can be done without column removal
Steering Column
Steering Wheel Removal Remove the horn button and steering shaft nut Scribe alignment marks on the steering wheel and the steering shaft Mount a wheel puller over the steering wheel Screw the bolts into the threaded holes in the steering wheel
Steering Wheel Removal Tighten the puller down against the steering shaft to remove the wheel
Steering Wheel Installation When installing the steering wheel, match any alignment marks Many steering shafts use a master spline so that the wheel only installs in one position Ignition lock, turn signal mechanism, and horn and cruise control slip rings are all accessible below the steering wheel
(Recirculating-Ball Type) Manual Steering Gearbox Service (Recirculating-Ball Type) Service involves the adjustment or the replacement of worn parts (bearings, seals, and bushings) Gearbox repair or overhaul may be necessary when adjustment will not provide proper operation
Gearbox Adjustment Two basic adjustments are performed on manual recirculating-ball gearboxes: Worm bearing preload preloads the bearings to ensure that the worm shaft is held snugly in the housing Over-center clearance controls the amount of lash between the pitman shaft gear and the teeth on the ball nut
Gearbox Adjustment
Worm Bearing Preload Adjustment Disconnect the pitman arm Loosen the pitman shaft over-center locknut and adjusting screw Using a torque wrench or spring scale, turn the steering wheel slowly from side-to-side
Worm Bearing Preload Adjustment Compare the required force to specs If needed, tighten or loosen the adjustment nut
Over-Center Clearance Adjustment Center the steering gear in its travel Preload is produced in the center of travel to avoid steering wheel play during straight-ahead driving
Over-Center Clearance Adjustment Loosen the locknut and bottom the adjustment screw lightly
Over-Center Clearance Adjustment Use a torque wrench or spring scale to measure the amount of force needed to move the shaft back and forth through center Tighten or loosen the adjusting screw until the amount of force needed to move the shaft is within specs Tighten the locknut after adjustment and recheck the required force
Over-Center Clearance Adjustment
Steering Linkage Service When your inspection finds worn steering linkage parts, new parts must be installed
Steering System Inspection
Idler Arm Service Idler arm wear will cause play in the steering wheel To check an idler arm, force it up and down using a spring scale When the specified force is applied to the spring scale each way, note the idler arm movement and compare to specs e.g. at 20 lbs (9.0 kg) of force, maximum 1/4” (6.5 mm) travel
Idler Arm Service To replace the idler arm, remove the cotter pin and castle nut Use a fork tool or puller to force the ball stud out of the hole in the center link Unbolt the idler arm from the frame Install the new part Torque the idler arm to specifications Install a new cotter pin
Tie-Rod End Service Tie-rod end wear will cause steering play To remove a tie-rod end, separate the tie-rod end from the steering knuckle or center link
Tie-Rod End Service Use a fork or puller to separate the tie-rod end from the steering knuckle
Tie-Rod End Service Loosen the adjusting sleeve, and count the number of turns required to remove the tie-rod from the sleeve
Tie-Rod End Service Install the new part the exact same number of turns Install the tie-rod ball stud into the center link or steering knuckle Tighten all of the fasteners to specs and install a new cotter pin Check toe adjustment with an alignment machine
Power Steering System Service Service involves the adjustment or the replacement of worn bearings, seals, and bushings Hoses, a pump, a power piston, and a control valve are added these parts can require repair or replacement
Power Steering Leaks To check for leaks, wipe fluid-soaked areas clean Have a helper idle the engine and turn the steering wheel to the right and left Watch for leaks as the wheels are turned, raising system pressure
Leakage Points (Rack-and-Pinion)
Leakage Points (Linkage System)
Servicing Hoses Always check hose condition when servicing a power steering system High-pressure hoses are exposed to tremendous pressures over 1000 psi (6895 kPa) When installing a new hose, start fittings by hand Use a tubing wrench to tighten the hose fittings properly
Bolts, hoses, and brackets that must be removed when replacing a pump Pump Replacement Bolts, hoses, and brackets that must be removed when replacing a pump
Pump Service During a pump rebuild, clean and inspect all the parts Check the pump vanes, thrust plate, and pump ring (included in a pump rebuild kit) Replace all o-rings, gaskets, and seals Lubricate the components with fluid and reassemble the pump
Bleeding the System When hydraulic components are serviced, bleed any air out of the system Idle the engine and turn the steering wheel fully from side to side Check the fluid level often Cycling the system will force air from the steering gear, back to the reservoir
Electronic Assist Steering Service Refer to service manual diagrams, part locations, and electrical value charts Use a scan tool to check for diagnostic trouble codes Check scan data for input and output data that could help isolate a problem Perform pinpoint tests with a multimeter to verify the source of any problems