2001 mercedes slk 230 front top lock was leaking so i ordered one unfortunately on Amazon. Hose tips were different and could not lock them into place. I went to a local hydraulics shop and had cylinder shaft and seals from new one put into my old cylinder. It works well to unlock tô but seems to be missing pressure to lock without my helping with allen key. I check for kinked or squeezed lines but all is ok. . Any ideas out there ????