The strut started leaking fluid from the upper seal shortly after installation.

Do not use pliers or vise grips on the polished shaft. The use of pliers can cause scoring the highly polished chrome shaft. This will cause increased wear on the upper seals and in turn cause a hydraulic fluid leak from the shock or strut.

Do use a wrench (special tools are also available) to hold the shaft. There is a shouldered area near the top of the shaft, below the thread area, that is designed for use with a wrench.