Steering & suspension

Shimmy only over bumps, not otherwise

A shimmy that appears only when driving over bumps, but not on smooth roads, usually points to worn suspension components rather than a simple wheel balance issue.

Difficulty
Moderate
Time
1–3 hours to diagnose and repair
Pro cost
$150–$600

Symptoms

  • Steering wheel shakes specifically when going over bumps or rough pavement
  • Smooth and stable on flat, even roads
  • Noise sometimes accompanies the shimmy

Likely causes

  • CommonWorn shocks or struts unable to control wheel movement over bumpsWeak dampers let the wheel bounce and shimmy when disturbed by a bump instead of absorbing it smoothly.
  • PossibleWorn control arm bushings or ball jointsPlay in these components lets the wheel shift when hitting a bump, causing a shimmy.
  • PossibleWorn wheel bearingA bearing with play can shimmy when disturbed by an uneven surface.

What to do

  1. Note that the shimmy specifically happens over bumps and not on smooth pavement, which helps rule out a simple balance issue.
  2. Check shocks and struts for wear using a bounce test and visual inspection for leaks.
  3. Have a mechanic check for play in ball joints, control arm bushings, and wheel bearings with the car on a lift.
  4. Replace whichever worn component is identified.
  5. Test drive over similar bumps to confirm the shimmy is resolved.

Tools and parts

Shocks or strutsSearch: “shocks or struts for [your car model]”

When to call a pro

This pattern points toward suspension wear rather than simple balancing, so a shop inspection on a lift is the most reliable way to find the cause.

Safety

Generally low risk

Generally low risk for a careful person. Stop if anything looks different from what this guide describes.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.