How to tell if struts are bad by looking at them?
Bad struts usually show up as oil leaks on the shock body, a torn dust boot, or a bent or damaged shaft. You may also notice uneven tire wear, a nose-dive when braking, or excessive bouncing. A careful visual check combined with simple at-home tests can indicate when a strut is worn or failing.
Struts are a core part of the suspension system, integrating a shock absorber with the mounting point for the coil spring. When they wear out, ride quality, steering response, and braking can suffer. Some issues are visibly obvious, while others reveal themselves only under load or during a drive. The following sections outline what to look for and how to assess struts safely, along with guidance on replacement decisions.
Visual signs to look for
These are the most reliable indicators you can spot with the car on the ground or with wheels removed, without specialized tools.
- Oil or dark hydraulic fluid leaking from the strut body or around the dust boot.
- Torn, cracked, or missing dust boot, allowing dirt and moisture to reach the seal.
- Bent, dented, or scoring on the strut shaft or housing.
- Corrosion or rust on the strut body, mounting points, or fasteners.
- Damaged or worn coil spring seats or mounting hardware (if inspecting a strut-and-spring assembly).
- Loose or broken mounting points at the top mount or bottom mount.
- Uneven boot wear or fluid transfer onto tires or inner fender panels.
Bottom line: Visible leaks, boot damage, shaft damage, or mounting issues are red flags that warrant a closer look by a professional.
How to test and assess
In addition to what you can see, perform these checks to gauge how the struts are behaving under load and during a drive.
- Bounce test: With the vehicle resting on a level surface, push down firmly on each corner and release. The car should settle within one or two bounces. Excessive bouncing suggests worn seals or a degraded gas charge.
- Leak check during handling: While the car is on level ground, look for fresh oil around the strut seals after a short drive or after a wheel is removed.
- Ride height and alignment: Note if one corner sits lower than the others or if the car pulls to one side, which can indicate a failing strut or mounting issue.
- Road test: Drive over potholes, speed bumps, and rough pavement. Listen for clunks, knocks, or change in steering feel such as wandering or excessive body roll.
- Boot integrity check: During inspection, verify the dust boot remains intact; tears or cracks can accelerate seal wear and leak development.
Conclusion: If any of these checks produce abnormal results—persistent bounce, unusual noises, or signs of leakage—schedule a professional inspection. Driving with compromised struts can degrade braking, steering, and cornering safety.
Replacement considerations and safety
Strut replacement decisions depend on severity, vehicle design, and driving conditions. In many vehicles, struts are replaced in pairs (front pair or rear pair) to preserve balanced handling and ride characteristics. Typical strut life ranges from roughly 50,000 to 100,000 miles, but factors such as road conditions, load, and maintenance impact longevity. Visible leaks, mounting damage, or significant wear are strong signals to repair sooner rather than later.
DIY vs professional service
Replacing struts requires proper tools, alignment, and torque specs. If you do not have the experience or equipment, have a trained technician perform the replacement to ensure safe installation and correct wheel alignment.
Summary
Key indicators of bad struts include oil leaks on the strut body, damaged dust boots, bent or damaged shafts, and failing mounting points, along with signs like uneven tire wear and poor handling. Use a combination of visual checks and basic tests to assess condition, and seek professional service when signs appear. Replacing struts in pairs is common to maintain balanced handling and safety.
