Brake slider pin's : installed pushed in or out ?

[naimc]

Every year I disassemble my brakes remove the slider pins and rubber boots, clean out with brake cleaner, blow dry with compressed Air re-grease with silicon based eze slide, re-insert pins without rubber boots to move grease around, remove pins reinstall rubber boots then slide the pin back.

Now for final step I have to options:
- Leave the air trapped inside the seal, this causes the pin to push outwards offering firm resistance so it will push away the caliper. As shown with my pick on the top. ( I think I do this every year)
Or
As seen on the bottom slider, push the pin slider pin in, then using a metal pick pry the rubber boot to allow all of the trapped air to escape.

I have watched a ton of videos on the subject and I don't remember any details regarding this. This brake bracket is from the rear of the 2019 Highlander and the Official Toyota techstream assembly instructions do not cover this detail.

Over the years have leant the less slider pin is better so they move freely and don't get "hydro locked"

 

[Jetronic]

it doesn't matter, do it either way and check a day later....

 

[tasch72]

I spin the pins in their receiver holes to get as much air out (and grease in) as possible. I've lost two caliper brackets to seized pins before and I don't want to lose another over 50 cents in grease.

 

[Jetronic]

I spin the pins in their receiver holes to get as much air out (and grease in) as possible. I've lost two caliper brackets to seized pins before and I don't want to lose another over 50 cents in grease.

Grease is very important, however I found proper silicone grease works very well, and for a long time.

 

[eljefino]

I like the air, even though it burps out right away.

I leave a decent supply of extra grease in the folds of the bellows.

 

[LeoStrop]

@naimc , i have the exact same doubt every time.

I do the second method (bottom pin of your picture), because when i reinstall the caliper it is almost impossible to assemble with the slider pushing up. But i don't feel completely satisfied because when you push the pin all the way down and bleed all the air, it hardly moves up due the vacuum. I try to leave it in between.

 

[JeffKeryk]

Air is for breathing. Grease don't breath.

 

[KevinMalone]

Official Toyota techstream assembly instructions do not cover this detail

Then it likely doesn't matter

 

[tasch72]

Grease is very important, however I found proper silicone grease works very well, and for a long time.

i'm a big fan of syl-glide for slide pins. it doesn't dry up like antiseize

 

[SHOZ]

I have Brembos on the Gen Coupe. No pins to grease.

The Accent is with the typical badly designed Hyundai caliper. But I use a copper corrosion inhibitor on it. I take them apart yearly. This year is new pads, pins, boots and hardware.

 

[GSCJR]

antiseize

Does not belong anywhere where rubber is present.

 

[D60]

I doubt the boots are rated for pressure and I worry they may "lose a bead" when burping on their own.

I never leave air in if I can help it.

 

[WobblyElvis]

The rubber boot won't hold any air. The rebound is caused by air trapped at the end of the pin down the blind hole. If grease gets down the bottom of the blind hole, it caused a hydro-lock and the pin cannot be pushed in all the way. Lube the pin before inserting, do not put grease down into the caliper as it will be pushed to the bottom when inserting the pin.

 

[doitmyself]

For what it's worth, I "burp" the rubber boot to release excess air. My thought is that it would normalize by itself, so it probably does not matter either way.

 

[buck91]

I burp them. Easier to reinstall and less void space for fluid to creep into.

 

[naimc]

it doesn't matter, do it either way and check a day later....

I like short and brief, thanks then I went back and looked at the boot and It's notched for air to escape :

Now I get it, the pin is only acting as a rail, whereas I thought it role was spring to put back the caliper. ( that makes no sense I know but it's what I though) I won't leave any air trapped in the future as it will be ejected anyways.

 

[KrisZ]

I’ve done it both ways and it makes no difference other than with air, the pin will push slightly against the bracket, which may have inhibit the installation a little bit.

Edit:
Do you actually disassemble the brakes every year and clean them out?

 

[supton]

I clean up the brakes once a year (sometimes twice) and have not seemed to "need" to pull the pins out. They're always "stuck" or really stiff. But pulling on them a few times, just working the grease, restores operation. I don't recall it being better if Sil-glyde was in there. Maybe once I've pulled the pin out and found rust in there, but usually the grease is in there, just not free. Pulled them out too many times only to find what looks like fine grease, so I have not bothered lately.

I usually get years out of brake pads so I'm guessing there is little movement and the grease just takes a set?

 

[Tman220]

Have you ever taken a brake caliper a part where there was still air pressure trying to push the pin out?..... Exactly! Don't over-think this. I like to burp mine for no other reason other than the calipers are easier to install when the pins aren't trying to eject themselves and stretching out the rubber boots.

 

[KrisZ]

I clean up the brakes once a year (sometimes twice) and have not seemed to "need" to pull the pins out. They're always "stuck" or really stiff. But pulling on them a few times, just working the grease, restores operation. I don't recall it being better if Sil-glyde was in there. Maybe once I've pulled the pin out and found rust in there, but usually the grease is in there, just not free. Pulled them out too many times only to find what looks like fine grease, so I have not bothered lately.

I usually get years out of brake pads so I'm guessing there is little movement and the grease just takes a set?

Whatever grease you’re using is hardening up.
Good grease will not do what you’re describing.