1. use must use brake grease to lube sliders.
Normal grease will swell the "o-rings" and need to replace them.
Is normal that slider need some force but really stuck then big problems.
See my Cave, Brake Service
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
The Ogre's Fiero Cave (It's also at the top and bottom of every forum page...)