[rsanges]

This is regarding the front brakes on my 2015 Trailhawk.

About once a year (when I switch between summer and winter tires -either way) I pull my calipers off and lubricate the slide pins with the Permatex purple "extreme" brake lube.
For the last couple of seasons, when I unbolt the calipers, the slide pins (top and bottom on both sides) won't slide by hand. They require a tool to grab them and slowly work them out of the carrier.

So, here's the thing... Once I get them out and moving they slide in and out super easily. Just the pressure built up by the slide pin retracting is enough to force them back out (like a hydraulically locked piston), but until they are freed up they are as stiff as frozen sh*t. I can't imagine they are allowing the caliper to move back and forth properly. When I get them out, they still have purple grease on them. It doesn't appear contaminated and the slide pins don't show any sign of unusual wear. Plus, it's all four front slide pins acting the same.

I read about bent slide pins online, but I don't think that is my issue because after they are moving - they move super easily. I pull them out and regrease them. Even before I regrease them, once they are freed up they move like butter. As they go back in they seem like happy campers, but come to the next inspection- they won't budge without some force from channel lock pliers.

I do the same with the rears and they have always been smooth as silk upon initial inspection.

I work on a lot of mechanical things, but I'm really just a shade-tree mechanic and don't have a ton of experience to draw on. What do you people think is going on with my front slide pins? Should I just get new ones and see if there is an improvement? Is this normal (it's not in my experience with other vehicles)? Looking for your opinions. Thanks.

 

[XFiber]

What do you use to clean off the pins before re-lubing them?
Have you tried going over the pins with a mild Scotch-Brite pad after cleaning?
Does temperature have any effect on them? I.E warming them with a heat gun before removing them.
How does the inside of the slider look?

 

[rsanges]

Thanks, XFiber.
I use a shop rag to clean them off. It appears I'm cleaning off the grease I just put in. I really don't put much effort into cleaning them. Maybe that's my problem.
Good question about the temperature. I've never needed to use heat. The force required to get them out is not ridiculous - just way more than a slide pin should need. Maybe I'll throw some heat on the carrier at the next inspection and see if they free right up.
I have never looked inside the carrier. I will attempt next time, but I assume it's going to be a small, greasy, dark hole.

I appreciate your thoughts.

 

[XFiber]

Thanks, XFiber.
I use a shop rag to clean them off. It appears I'm cleaning off the grease I just put in. I really don't put much effort into cleaning them. Maybe that's my problem.
Good question about the temperature. I've never needed to use heat. The force required to get them out is not ridiculous - just way more than a slide pin should need. Maybe I'll throw some heat on the carrier at the next inspection and see if they free right up.
I have never looked inside the carrier. I will attempt next time, but I assume it's going to be a small, greasy, dark hole.

I appreciate your thoughts.

If it frees up after warming them then you'll know that they are probably working normally. Have you tried spraying Brake Cleaner in those "small, greasy, dark holes" and then twisting a rag or paper towel around inside to clean it out?
I had to disassemble and clean out old dielectric grease from a few switches on my Goldwing because is just about set up like concrete and the tiny parts inside wouldn't move unless it was very warm and sitting in the sunlight.

 

[rsanges]

Good ideas. I will use brake cleaner on them next time.

 

[georgef]

About once a year (when I switch between summer and winter tires -either way) I pull my calipers off and lubricate the slide pins with the Permatex purple "extreme" brake lube...

Even though the Permatex purple claims to be safe for rubber parts, there are reports (on the internet) of it causing swelling on certain rubber components. Maybe the Permatex is swelling the rubber sleeves on the slide pins.

Please note that even though I do use the purple Permatex on the brake pad clips and the back of the brake pads, I have always used Sil-Glyd brake lubricant on the slide pins, so I don't have any personal experience with the Permatex on the slide pins.

 

[XFiber]

Even though the Permatex purple claims to be safe for rubber parts, there are reports (on the internet) of it causing swelling on certain rubber components. Maybe the Permatex is swelling the rubber sleeves on the slide pins.

If the rubber dust boots are swelling, don't you think they would be loose instead of binding?

Please note that even though I do use the purple Permatex on the brake pad clips and the back of the brake pads, I have always used Sil-Glyd brake lubricant on the slide pins, so I don't have any personal experience with the Permatex on the slide pins.

Have you considered trying Lithium Grease?

 

[georgef]

If the rubber dust boots are swelling, don't you think they would be loose instead of binding?

Not the dust boots, I'm talking about the rubber sleeve on the slide pins:

Have you considered trying Lithium Grease?

Sil-Glyd has always worked well for me, is there a reason I should switch to Lithium Grease?

 

[rsanges]

What's the function of that sleeve, and why is it only one one of the pins?

 

[georgef]

What's the function of that sleeve, and why is it only one one of the pins?

It's there to reduce noise (rattle), I don't know why it's on only one pin, but the manufacturer must believe one is sufficient. I've read of people using two solid pins to prevent problems with the rubber sleeves.

 

[XFiber]

Not the dust boots, I'm talking about the rubber sleeve on the slide pins:
View attachment 2396355640


Sil-Glyd has always worked well for me, is there a reason I should switch to Lithium Grease?

Well, that was news to me!! The only parts I found didn't show the pin on the left. Although some rebuild kits did have the rubber sleeves in them. Sil-Glyd would be a better product for that application as the lithium grease will interact with the rubber.

 

[rsanges]

Mine has that sleeve on one pin (each side). I will try Sil-Glyd next time. I'm not sure if anything has gone wrong with the sleeve because the pin does move smoothly after I get it moving. Both pins (on both sides - with or without the sleeve) behave the same.
I appreciate your suggestions. I'm probably not taking any action now until spring. Unless someone has a revelation regarding this, we can probably let this thread die for now. Thanks!