Depending on the year model for your Powergear Hyd jacks. OLDER at least over 20 years have NO grease Zerks at the bottom of the cylinder. Jacks newer or rebuilt with the Powergear rebuild kit will have a grease Zerk on the bottom of the cylinder just above the footpad. THIS Zerk you install standard lube grease until the cylinder seal just starts to bulge. This grease will usually fix any
slow or sticking retract problems on Powergear HYD jacks. Other than this, just keep the inner cylinder clean and shiny. Doug
Video at 1 minute 30 seconds shows the Powergear Zerk.
https://www.youtube.com/watch?v=nCpHnFmp0f4