Troubleshoot alignment, tire wear, odd suspension noises, etc.

General Auto Repair

Suspension systems can be classified into two subgroups: dependent and independent. These terms refer to the ability of opposite wheels to move independently of each other.

An independent suspension allows all four wheels to independently rise and fall on their own without affecting the opposite wheel. Suspensions with other devices, such as anti-roll bars that link the wheels in some way are still classed as independent. This type of suspension is commonly found in sports cars and high end exotics.



A dependent suspension normally has a beam (a simple 'cart' axle) or (driven) live axle that holds wheels parallel to each other and perpendicular to the axle. When the camber of one wheel changes, the camber of the opposite wheel changes in the same way (by convention on one side this is a positive change in camber and on the other side this a negative change). De Dion suspensions are also in this category as they rigidly connect the wheels together.

A third type is a semi-dependent suspension. In this case, the motion of one wheel does affect the position of the other but they are not rigidly attached to each other. A twist-beam rear suspension is such a system. Wikipedia:Suspension

This is general trouble shooting information. This article is not intended to be specific to any unique situation or individual vehicle configuration. The purpose of this Trouble Shooting information is to provide a list of common causes to problem symptoms.

Front End Noise

• Loose or worn wheel: See Wheel Bearing Adjustment in SUSPENSION
• Worn shocks or shock mountings: Replace struts or strut mountings
• Worn struts or strut mountings: Replace struts or strut mountings
• Loose or worn lower control arm
• Loose steering gear-to-frame bolts
• Worn control arm bushings
• Ball joints not lubricated: Lubricate ball joints

Front Wheel Shake, Shimmy, or Vibration

• Tires or wheels out of balance: Check tire balance
• Incorrect wheel alignment
• Drive shaft unbalanced: Check drive shaft balance
• Loose or worn wheel bearings
• Loose or worn tie rod ends
• Worn upper ball joints
• Worn shock absorbers: Replace shock absorbers
• Worn strut bushings: Replace strut bushings

Car Pulls to One Side

• Mismatched or uneven tires: Check tire condition
• Broken or sagging springs
• Loose or worn strut bushings
• Improper wheel alignment
• Improper rear axle alignment: Check rear axle alignment
• Power steering gear unbalanced
• Front brakes dragging

Abnormal Tire Wear

• Unbalanced tires: Check tire balance & rotation
• Sagging or broken springs
• Incorrect front end alignment
• Faulty shock absorbers: Replace chock absorbers

Scuffed Tires

• Toe-In incorrect
• Suspension arm bent or twisted

Springs Bottom or Sag

• Bent or broken springs
• Leaking or worn shock absorbers: Replace shock absorbers
• Frame misalignment: Check frame for damage

Spring Noises

• Loose "U" Bolts
• Loose or worn bushings
• Worn or missing interliners

Shock Absorber Noise

• Loose shock mountings: Check & tighten mountings
• Worn bushings: Replace bushings
• Air in system: Bleed air from system
• Undercoating on shocks: Remove undercoating

Car Leans or Sways on Corners

• Loose stabilizer bar
• Faulty shocks or mountings: Replace shocks or mountings
• Broken or sagging springs

Shock Absorbers Leaking

• Worn seals or reservoir tube crimped

Broken Springs

• Loose "U" bolts
• Inoperative shock absorbers: Replace shock absorbers

General Auto Repair

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