What is a Liftgate Glass Support Strut?
Many of the vehicles that feature a liftgate are fitted with a window (the liftgate glass) that swings outward and upward for easy access to the rear cargo compartment. When opened, the glass is supported by a pair of pneumatic arms, or struts. These liftgate glass support struts become fatigued with age and constant wear, and occasionally need to be replaced.
How do Liftgate Glass Support Struts work?
A liftgate glass support strut is a long, slender cylinder with a solid rod running through the center as a sort of plunger. The strut is gas filled (pneumatic) so that when the rod is pushed into the cylinder, the gas is compressed. This serves to force the rod out of the cylinder, thereby extending the length of the strut. The action is similar to that of a shock absorber. The force exerted by the struts is matched to the weight of the glass and the leverage produced when it is open. When the glass is closed, the struts are compressed. When the glass is unlatched, the struts naturally decompress and extend to open the glass.
What are the symptoms of a bad Liftgate Glass Support Strut?
The primary symptom of failing support struts is nearly always a window that will not stay open. Over time, the struts wear out and weaken, and the force they are able to exert on the glass diminishes. Most vehicle owners first notice that the glass does not open as quickly as usual when the struts are near the end of their useful life. As the condition worsens, the window will tend to fall down when opened, though the problem may, for a time, be intermittent. Cooler temperatures tend to exacerbate the problem.
Can I drive with a bad Liftgate Glass Support Strut?
If the liftgate glass support struts fail, there is no reason that the vehicle cannot be driven. But failing support struts, whether on the liftgate glass, on the liftgate itself - or on a hood or deck lid - pose a risk for head and neck injury. Care should be exercised if the struts are worn past their ability to keep a body panel supported.