Common signs are a hood that won’t stay open, drops suddenly, lifts slowly or feels stiff, or shows leaks or misalignment; if you notice any of these, the hood struts may be failing and require inspection or replacement.
What hood struts do and how they fail
Function of hood struts
Hood struts (gas springs) counterbalance the weight of the hood, letting it stay open at a safe height without you holding it. They also control the speed of the hood’s motion so it doesn’t slam shut or pop open too quickly.
Common failure modes
With time and repeated cycles, the gas inside the strut can lose pressure, seals can degrade, or mounting points can corrode or wear. This can lead to a weak hold, a sluggish lift, or a sudden drop. Physical damage, bent brackets, or misalignment can also cause uneven operation between the two sides.
Signs your hood struts are failing
Here are the most common indicators that your hood struts are losing their pressure or are damaged.
- Hood won’t stay open at any height and starts to close on its own.
- Hood lifts slowly, feels stiff, or requires extra effort to hold up.
- You hear a hissing sound or notice oil/gas leakage around the ends of the struts.
- The hood lifts unevenly or on one side, suggesting mounting or alignment issues.
- Visible damage, rust, or corrosion on the strut body or its mounting points.
If you notice any of these signs, inspect both struts and their mounting points and consider replacement if performance is unreliable or dangerous.
How to test hood struts at home
Use a simple, step-by-step check to confirm suspected failure by observing lift and hold behavior, listening for leaks, and inspecting hardware.
- With the hood fully closed, gently lift to a safe height and release. The hood should stay near that height if the struts are good; if it continues to rise or falls quickly, the struts may be weak.
- Repeat on both sides, since most cars have two struts. They should feel similar in resistance and hold, not one side stronger than the other.
- Inspect the seals and ends for signs of oil or gas leakage, cracks, or rust.
- Check the mounting points where the struts connect to the hood and the chassis for looseness, wear, or damage.
- Compare to new replacement struts if possible; if the old struts are noticeably weaker or fail to hold, replacement is advisable.
Consistent failure during this test means you should plan a replacement, ideally with the same model and specifications as the original.
Replacing hood struts
Replacing hood struts is a straightforward job for many cars, but it requires proper support for the hood and correct parts that match the mounting points and length. Expect replacement to take about 15-30 minutes per side with basic hand tools.
- Park the car on a flat surface, turn off the engine, and have a helper support the hood or use a prop rod. Safety first: never work under a loaded hood without support.
- Detach the upper ball stud from the hood side and remove the old strut from the hood mounting. Some designs use a retaining clip that must be pried off or released.
- Do the same on the lower mounting point, then remove the old strut from the chassis/fender side.
- Compare the old strut to the new one to ensure correct length and force rating. Install the new strut by attaching it first to the upper ball stud, then to the lower ball stud, following the manufacturer’s instructions.
- Reconnect any clips or bolts, check for secure fit, and slowly test the hood by lifting to a few predetermined angles to confirm even operation. If the hood drifts or shows binding, recheck alignment or consider a different strut model.
After replacement, check for proper hood alignment and ensure both sides operate smoothly. Dispose of old struts responsibly and consider testing again after a few days of use to confirm lasting performance.
Choosing the right replacement
To pick the right hood struts, match the length, mounting style (end-mounted ball studs), and the force rating (often measured in Newtons or pounds) to your vehicle’s specifications. The owner’s manual or a parts catalog can confirm the correct spec. If in doubt, bring one old strut to an auto parts store or consult a professional.
Safety and maintenance tips
Regular inspection can extend hood strut life and prevent surprise drops. Look for leaks, corrosion, or bent mounting points at least once a year or during major service intervals. Replace both struts in pairs to ensure balanced support and avoid uneven wear.
Summary
Hood struts are essential for safe, hands-free opening of the hood. Signs of failure include the hood dropping, slow lifting, or leaks, and testing should be done carefully. Replacing with the correct rated units and ensuring proper installation will restore reliable operation. If you’re unsure, seek a professional mechanic.