Hood lift supports are an under the hood component found on many road going cars and trucks. As their name implies, the hood lift supports are the small, usually gas charged, cylinders that are used to support the hood when it is opened. When the hood is opened the lift support is extended and the pressure inside the cylinder supports the weight of the hood. A lift support is strong enough to support the weight of the hood without retracting under the weight. Only with the additional leverage of the hood, should the lift support be able to be collapsed.
When a lift support fails or begins to have issues, it can lead to problems with keeping the hood supported. Usually a faulty lift support will produce a few symptoms that can alert the driver of a potential issue.
1. Hood slowly closes on its own
One of the first symptoms of an issue with the lift supports is a hood that will slowly begin to close on its own when opened. Lift supports operate by using pressurized gas sealed inside of a metal cylinder to hold the weight of the hood. Over time, however, the seals can wear out and begin to leak slowly over time. Once enough pressure has leaked from cylinder it will no longer be able to properly hold the weight of the hood, which will cause it to slowly lower until it eventually closes.
2. Hood suddenly closes on its own
Another symptom of faulty lift supports is a hood that suddenly closes on its own. A faulty lift support may have worn seals that may appear to be able to support the hood, only to suddenly give out, causing the hood to slam shut. This will make working under the hood unsafe, as the hood can fall at any moment while someone is working underneath the hood.
3. Hood does not stay up at all
Another, more obvious, symptom of faulty lift supports is a hood that does not stay up at all. If all of the pressure leaks from the lift support it will not be able to support the weight of the hood at all, and the hood will close as soon as it is opened. This will make it impossible to work underneath the hood of the vehicle without some sort of prop to support the hood.
Most hood lift supports will last several years, and will not usually require replacement until after a vehicle enters high mileage. If you suspect that your vehicle may be having an issue with the hood lift supports have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if the supports should be replaced.
This article originally appeared on YourMechanic.com as Symptoms of Bad or Failing Hood Lift Support Shocks and was authored by Eduardo Ruelas.