User manual no help on the how. This is what I wrote earlier:Hi Kenny I will see if I have the user manual for it and hopefully a numpty like myself can do it without messing it up
Undo the threaded cap at the top of the lower tube, mine was really stiff and needed a plumbers wrench, I wrapped a piece of inner tube round it to protect it. Clean the tube and especially the inside of the cap, there is an o ring that sometimes gets stuck inside the cap. Press some light grease, I use SRAM Butter, into the top of the bottom tube and cycle the post a few times. Reassemble.