What is the Point in Rubber on Brake Sliders?

[HLxDrummer]

Alright I'm not sure what the terminology is, but why are there little rubber sleeves on the end of the sliders for the rear brakes? On a couple of cars I have done brakes on the calipers have stopped sliding and I take this all apart and clean it but I feel like the rubber really binds them up. For example a Civic I did had rubber on one bolt and not the other. The one without rubber went in nice and smooth and the other was pretty hard to push in.

Any info?
Thanks!

[vroom4]

To keep crap from getting into the slider space and binding it up?

[i3igpete]

the caliper pin's dust boot?

http://i.imgur.com/kbzq3Tb.jpg

[HLxDrummer]

Na not the dust boot.. It is on the other pin.. looks like this picture:

http://www.lukekailburn.com/media/chassis/brakes/caliperrebuild/100_2718.jpg

[vroom4]

Yea, thats the dust boot. If it wasnt there the dirt would stick right to the grease.

[Bloodlust182]

He is not talking about the boots, on the end of the portion that goes into the bracket there is a rubber "oring" looking piece. Im not entirely sure what it is for either.

[anyonebutme]

think it helps prevent knockback on sliding calipers, or reduces pad taper. Every sliding caliper I've taken apart has one pin with the rubber piece, never have seen a caliper than uses them on both.

[Keyan]

helps keep the caliper from freely rattling and moving around when assembled.

i remove them when i get the chance. usually after the caliper has bound up.

[HLxDrummer]

Gotcha, thanks guys!