How do you know struts are bad?
In short, failing struts reveal themselves through leaks, unusual noises, poor damping, sagging, or misalignment. This guide explains how to recognize bad struts across common contexts—cars, gas springs, structural elements, and aerospace—and what to do when you find signs of trouble.
Automotive suspension struts: the telltale signs
Most drivers notice issues first in ride quality and handling. The following indicators are commonly associated with worn or failing coil-over/strut assemblies in passenger vehicles.
- Leaks or seepage on the strut body, indicating worn seals or a failed gas-charged unit
- Excessive bounce, nose-diving during braking, or poor damping
- Tire feathering or uneven wear caused by compromised suspension alignment
- Unusual noises such as clunks, bangs, or squeaks when driving over bumps
- Visible damage, rust, or bending of the strut housing
- Changes in steering feel, including pulling to one side or increased body roll
When these signs appear, have a qualified mechanic inspect the suspension to confirm strut condition and prevent further damage to the vehicle.
Gas struts and shock absorbers in everyday use
Gas struts (found in hatchbacks, tailgates, office chairs, and some furniture) wear differently from automotive dampers. Look for these symptoms of failure.
- Struts that do not stay open, or close slowly or unevenly
- Visible corrosion or oil/gas leaks around the cylinder
- Unstable or sagging hinges that do not hold their position consistently
- Excessive noise or a hiss when moving the hinged surface
Gas struts can often be replaced relatively easily. If you notice persistent failure to hold a position or leaking, consult the manufacturer’s guidelines or a skilled technician for replacement.
Structural and architectural struts
In buildings, bridges, and other structures, struts provide essential support. Signs of distress can indicate safety risks that require professional evaluation.
- Visible corrosion, rust stains, or pitting on metal struts
- Cracks, bending, or deformation at joints or connections
- Doors or windows that stick, misalign, or sag under load
- Unusual creaking, popping, or shifting sounds during wind or traffic loads
- Settlement or sagging floors, leaning walls, or uneven surfaces near structural braces
Any indication of structural stress warrants a professional structural engineer or licensed contractor assessment immediately. Do not ignore changes in alignment or visible damage.
Aircraft and other specialized struts
In aerospace and other high-stress systems, strut integrity is critical for safety. Signs of degradation should prompt maintenance by certified technicians using approved procedures.
- Visible cracks, corrosion, or deformation in load-bearing struts
- Joint looseness, misalignment, or abnormal vibration during operation
- Leakage in hydraulic or pneumatic struts (where applicable)
Because of potential safety risks, avoid inspecting or attempting repairs beyond basic checks; rely on approved maintenance schedules and official directives.
What to do if you suspect a bad strut
If you notice any of the signs described above, prioritize safety and seek professional assessment. The following steps are generally recommended across contexts.
- Limit use of the affected equipment or structure and avoid stressing the suspected strut.
- Schedule an inspection with the appropriate expert (mechanic, structural engineer, or aerospace maintenance technician).
- Document signs and timing (photos, noises, symptoms) to aid diagnosis.
- Follow the professional’s guidance, which may include repair, replacement, or further testing.
Never attempt critical repairs on load-bearing or safety-critical struts unless you are qualified and authorized. Safety should always come first.
Summary
Struts provide essential support across many systems. Common warning signs include leaks, visible damage, abnormal noises, poor damping or hold-open behavior, and misalignment. Treat any potential failure as a safety concern and have a qualified professional assess and, if needed, replace or reinforce the struts to restore reliability and safety.
