When closing the liftgate during the normal course of use, the liftgate support cylinder on the passengers (right) side failed (metal ball joint snapped where it connects to the liftgate), causing the support cylinder to fall between the liftgate and the rear tail light. Without this support cylinder in place, the liftgate did not receive enough support from the left side support cylinder and rapidly fell, smashing the right support cylinder into the right tail light, shattering the tail light assembly. Additionally, there was no way to secure the liftgate with the broken support cylinder still attached to the body of the vehicle. Fortunately, my wife had a ratchet set in the vehicle from the last time this happened and was able to remove the two bolts connecting the support cylinder to the body of the vehicle. Had she not had the ratchet set in the car, she would have had to drive the vehicle somewhere else with the liftgate unsecured. This was an extremely dangerous situation as the liftgate could have seriously injured someone who may have been underneath when the support cylinder failed. Additionally, the way the support cylinder is installed, when it fails, it WILL break the rear tail light assembly. The support cylinder has nowhere to go but across the tail light. The problem was not reproduced by a dealer, but the same thing happened to the support cylinder on the other side (driver, left side) of the car only 5 months earlier. We have only had the car 8 years. There is no reason this component should fail in 8 years when using the liftgate under normal operating conditions. There are no warning signs that this will happen. It simply just fails and the liftgate comes crashing down. I did not have a mechanic look at the issue as it simply requires a new support cylinder (M part at Subaru costs $138). I was able to replace the cylinder when the part arrived, but my tail light is still shattered. I will have to replace that as well ($289 at Subaru).