Steering System Diagnosis and Repair Flashcards
What do steering column component malfunctions often contribute to?
Steering column component malfunctions often contribute to binding, hard steering, looseness and excessive steering wheel play.
What should you do when experiencing excessive wander?
Check for steering column shaft adjustment, worn upper or lower bearings, or worn U-joint or flex coupling.
When worn steering column bushings or bearings, leave excessive lash in the linkage, what will it cause?
A loose feeling in the steering wheel when driving straight, noise when hitting a bump in the road because the bushing acts as a cushion, and a pull to the left or right while driving because the wheels will drift to the pitch of the highway.
When experiencing no steering recovery, what should you look for?
Look for lack of lubrication in the U-joint or flex coupling, worn upper or lower bearings, bent steering shaft or U-joints not installed properly.
What might the cause be when experiencing excessive steering wheel movement?
The cause might be a loose steering wheel, worn U-joint or flex coupling, loose steering gear, a loose pitman arm, loose or worn steering linkage components, or steering gear out of adjustment.
What should you inspect when experiencing steering column binding?
Inspect for worn or seized U-joint or flex couplings, steering column bearings binding or misaligned, bent steering shaft, or U-joints not properly installed.
What should you refer to if component repair or replacement is necessary?
Refer to OEM procedures.
What do most steering systems use to allow the shafts to mount on an angle?
Most steering systems use Universal joints (U-joints) to allow the shafts to mount on an angle.
Describe the function of the intermediate shaft.
- The intermediate shaft used on most truck steering systems, runs from the lower end of the steering column shaft to the steering gear input shaft.
- The intermediate shaft connects to the steering gear input shaft with either a flex coupling or U-joint.
- In some cases, the upper end of the intermediate shaft is also equipped with a U-joint.
- With this configuration, the lower, coupler assembly can be rebuilt or is replaceable while the upper coupler assembly is not.
What is required to prevent the possibility of speed fluctuations caused by shaft U-joints operating at an angle?
Proper phasing is required.
What is the required phasing of most steering shafts during installation?
Most steering shafts require phasing both shaft yokes on the same plane during installation.
-This ensures that the steering gear and the steering wheel operate in unison even though the shaft speed may fluctuate.
What should you not do when testing a linkage joint for excessive wear?
- When testing a linkage joint for excessive wear, you should not compress the steering column U-joint with a C-clamp or large pliers.
- This process will compress the tension spring in the joint and give the impression there is wear in the joint.
What should you do to identify excessive wear excessive wear when testing a linkage joint?
Simply push against the joint with the force you can create with your hands.
What should steering columns bearings and bushings be checked for?
Steering column bearings and bushings should be checked for wear, noisy operation, and binding during operation In addition, steering shaft seals and boots should be inspected for proper installation and damage.
Since steering shaft, joint, and bearing service varies depending on the steering column type what should you do?
Always refer to the instructions in the manufacturer’s service manual for the proper repair/replacement procedure.
What are the parts of cab air suspensions?
Cab air suspensions contain one or two air springs, two shock absorbers, and a leveling valve.
What is the function of the leveling valve?
The leveling valve maintains the proper air pressure in the air springs to provide the correct cab height.
How would you maintain the proper cab height?
You adjust the height control or leveling valve (similar to air suspension systems) to maintain the proper cab height.
Note: Suspension height should be set before any diagnostics are performed.
What should a visual inspection of the air bags include?
Should include looking for cracking or wear of the rubber component, piston condition and mounting, dirt accumulation around the piston, and exterior components that may come in contact with the bag or interfere with bag travel.
What should the shock absorbers be checked for?
Shock absorbers should be checked for proper mounting, leakage, and proper travel.
What should the leveling valve be inspected for?
The leveling valve should be inspected for proper mounting, leakage, and proper ride height adjustment.
How would you remove the steering wheel?
- To remove the steering wheel, begin by removing the hub cover and steering wheel retaining nut.
- Using a suitable puller, remove the steering wheel from the upper steering column shaft.
- Reinstall the steering wheel nut to prevent the steering column shaft from sliding our of the jacket tube. (if equipped).
What precautions should you take when removing the steering wheel?
Do not use a knock-off type steering wheel puller or strike the end of the upper shaft with a hammer. Damage to the steering shaft bearing may occur.
When should the steering wheel be centered?
When the front wheels are in the straight-ahead position.
What happens if the steering wheel is not centered?
- The sector shaft may not be contacting the high point of the ball nut. This condition causes erratic steering control.
- If the steering wheel is not centered, be sure the steering wheel is installed in the proper position on the steering shaft.
- after a toe adjustment, the steering wheel may require centering.
How would you center the steering wheel on an idler arm-type steering linkage?
The steering wheel is centered by rotating the tie rod sleeves with the proper tie rod sleeve rotating tool.
- If the steering wheel spoke is low on the left side, rotate the tie rod sleeves to shorten the left tie rod and lengthen the right tie rod.
- A one-quarter turn on the tie rod sleeves moves the steering wheel approximately 1 inch.
How would you center the steering on a heavy duty truck steering system?
- Centering the steering wheel on a heavy-duty steering system may be accomplished through an adjustable drag link if equipped.
- If not equipped with an adjustable drag link, ensure the front wheels are in a straight-ahead position.
- Disconnect the drag link from the pitman arm.
- Center the steering gear and check to see if the pitman arm is splined in the proper position.
- Check the measurement between the pitman arm bore and the steering control arm.
- Check the length of the fixed drag link to ensure it is the proper component.
- If correct, reinstall the drag link and then reposition the steering wheel on the steering shaft.
- Note: If a caster adjustment is required, it should be done before centering the steering system and wheel.
What are the the six conditions that the steering angle sensor must be re-calibrated as part of?
- Steering wheel replacement.
- Steering angle sensor replacement.
- Any maintenance that involves opening the connector hub from the steering angle sensor to the column.
- Any maintenance or repair work on the steering linkage, steering gear, or other related mechanism.
- Wheel alignment or wheel track adjustment.
- Accident repairs where damage to the steering angle sensor or assembly or any part of the steering system may have occurred.
What cautions should you take when replacing a steering wheel?
Use only OEM-approved steering wheels. Take care not to damage the steering angle sensor or interfere with its operation during installation.
Before inspecting steering components, what are the steps you should take?
> If possible, interview the driver to determine if the issue is ongoing or only occurs under certain conditions.
Road test the vehicle under the conditions described and try to duplicate the condition.
Pay particular attention to speed, load factors, directional issues, and noisy operation.
Tire inflation and suspension component condition may also play a role in steering system issues.
What can be the cause of power steering system “noise”?
Noise can be caused by various sources. A visual and audible inspection must first be performed to determine cause. (check belts, fluid level, mounts, etc)
What can be the cause of power steering system binding, and turning effort, Hard steering?
This can be the result of improper torque applied to any newly installed components; seized or under-lubricated moving components; improper phasing during the installation of shafts and/or U-joints; loose drive belts; misalignment due to wear. fatigue, or collision damage; or improper servicing of power steering filters.
What can be the cause of power steering system looseness?
Improper torque specifications (i.e. steering box pre-load) and worn improperly installed components can lead to excessive steering wheel movement.
What can be the cause of power steering system darting/oversteer?
Loose steering components and/or a misadjusted power steering gear may cause this condition. Tire inflation, load factors, and suspension component condition should also be inspected.
What can be the cause of power steering system reduced wheel cut?
May be caused by misadjusted power steering gears, wheel stops not being adjusted properly, or bent mechanical steering components.
What can be the cause of power steering system Wheel kick?
May be caused by air in the hydraulic system, loose steering gear mounting worn stereing linkage, front wheel bearings not adjusted or worn, improper steering gear adjustment, damaged or worn steering gear components, or worn or missing poppet valves.
What can be the cause of power steering system pulling and non-recovery?
May be a result of a variety of mechanical and/or hydraulic issues. In addition, front-end alignment, tire inflation, load factors, and road conditions may also have an effect on the steering components.
When determining the cause of pulling and non-recovery complaints, check tire pressures, wheel bearing adjustments, suspension components, and ride height adjustments in addition to inspecting steering system operation and components. If no mechanical or hydraulic issues are found, perform a front and rear axle alignment factors may be contributing to the issue.
What can be the cause of power steering system fluid leakage and aeration?
Inspect for visual signs of external and internal fluid loss. Correct as necessary.
An overfilled reservoir may be the result of a restricted high-pressure line.
An air leak on the low-pressure side would lead to air being ingested into the hydraulic system, which would lead to both overfill and foaming (aeration).
What will cause the steering wheel to become more off center over the course of 500 miles?
A loose sleeve clamp on the drag link adjuster with damaged adjusting threads.
What will cause steering wheel freeplay?
A worn steering shaft U-joint or an out-of-adjustment steering gear.
What will cause a wheel and tire not to return to the straight-ahead position during a front axle and linkage-binding test?
Defective kingpins or kingpin bearings.