April is when I do all my maintenance and yesterday figured that I would replace the front brake pads. I’ve done it several times before usually along with the rotors but it hasn’t been that long and I was surprised to be hearing the scraping noise a few months ago. Anyway, the caliper bolt dust boots have never been replaced so this time I spent more on a higher quality brake pad set that included the boots - which was not the case in all the previous sets that I had installed. So when I went to take everything apart - the bolts were badly stuck and it was a bear getting them out. But then - I could not figure out how you are supposed to get the boots out. It hadn’t occurred to me that this was not only never shown in any video on the job that I have ever seen, but I didn’t think it would be a problem - until yesterday when I went to get them out. Are you just supposed to grab them with a pliers and totally destroy them when you pull them out? After getting worried that I would mess things up, I just decided to keep the new ones in the package and just lube the old ones up using my little finger inside along with the actual pins. The stuff I bought specifically for this is a little green PERMATEX caliper bolt lube - which doesn’t work very well based on how stuck the bolts were. Then I looked at the old pads - major uneven wear. Like one side was almost new and the other barely anything left - which must be where the noise was coming from.
So my questions are: 1. How are you supposed to get the boots out and the new ones in? and 2. Am I using the wrong stuff for greasing the bolts and the inside of the boots? That’s what this stuff is for and seems to act more like glue than grease. I won’t be taking the front apart again for at least a year. After I got done, my parking/emergency brake was way too lose so now I have to try and hope I can adjust them otherwise it won’t pass the state inspection.
After having used this PERMATEX caliper pin lube for the last brake job and again applying it to the sleeves and pins this time - I was concerned about to do some research. I had spent more on this special stuff over cheaper generic grease precisely because the auto parts guy told me it was the best - and I didn’t want to take any chances. Well now in the past 24 hours, I am finding out this stuff is supposed to be for metal-to-metal contact only - no rubber. That would have been nice to see on the actual product which I read closely yesterday and no mention of it - only on their product (Permatex) website. So now I am faced with either leaving it in there or basically re-doing the entire brake job all over again - and this time throwing away the ruined rubber sleeves/boots and so I would have to know for sure how to get them out and get the new ones in.
Any ideas or suggestions or opinions about the lube or what to do? I probably won’t have time to do it for a while. Too many other things that have to get fixed first.
You car doesn’t have sealed guide pins. The rubber parts you purchased are “spool” shaped isolators to make up for poor machining tolerances and brake noise issues. They contain a metal sleeve that the attachment bolt rides on the allow the caliper to float. It is a poor design and one of the reasons why not even GM cars no longer use GM-Delco brakes.
Push the sleeve out of the rubber, push the rubber out of the caliper. Reverse to install a new “spool” and sleeve. Use the Permatex grease you bought, it is the right product.
You might need to use a little pick or pocket screwdriver to remove the boots from the caliper. Afterwards, clean the bore out with a brush, then lube the new boot with the grease and install the new boots. Double check that the boots are properly seated at both ends
Depending on the source of your brakes, some places offer a hardware kit. These are not expensive when compared to the cost of the pads and rotors and should be purchased when you get the pads.
As for the caliper pin boots. Not sure if you have the type where the caliper pin has the threads next to the bolt head and the pins protrudes from there or if the pins are actually a tube that slides and the mounting bolt goes through the middle of the tube. The first type has one boot per pin, the second has two.
In either case, you remove the boot by squeezing it near the base, The boot has an external lip that fits into a groove about an 1/8" below where the bore for the pin starts. You will see this when you squeeze it. They can be a little difficult at first as they kinda get attached to the groove, sometimes due to rust, but they will come out easily without any damage.
Your caliper on the side that doesn’t look worn may be frozen. That would mean the other side was doing all the braking and wore out prematurely.
If that is the case, you would want to replace the caliper. Conventional wisdom is that they are replaced in pairs, but I had a ,eft rear caliper that froze from rust very prematurely at 21000 miles and the other side looked good so I replaced just the one and they have been wearing evenly. I check mine in May or June, whenever it hits the upper 70s.
I used brake lube for the caliper slides on my Corolla as I recall. I think a little packet of brake grease came with the new pads. The service data I’m seeing for the 2001 Cav says to coat the inside of the caliper bushings with silicone grease. I see no explanation how to install or remove the dust boots. I presume if they don’t come off easily then they have to be destroyed during removal and new boots installed on re-installation.
On my Corolla the recommended caliper bushing lube is either a lithium soap base glycol grease, or a high temperature silicone grease (which seems to be the preferred grease now). I seem to recall that I had to rotate the dust boots as I installed them to get them to seat properly.
I believe I used a copper-based brake grease in years past, came in a can, when lubing the brake shoe sliding points on my truck. Now-a-days the replacement shoes and pads tend come with a packet of brake grease. I just use whatever is in the packet.
I just got a set of pads to put on when I get around to it and it had a very small packet of grease. I have a tube of synthetic brake grease though that I’ve had for years and don’t imagine I’ll ever use up. I use it on the slides and on the pads where indicated. I’ve also got the anti-squeal stuff that I use on the back of the pads.
Well after another 24 hours of searching online, it is pretty clear the problem is what I feared - this .5oz tube of Permatex Ultra Disc Brake Caliper Lube that I spent $5 on after being told it is the best from the auto parts guy - and that nowhere on the tube in the fine print or anywhere states that it is for metal-to-metal surfaces only and lacks any sort of BIG WARNING like it should NOT be used on rubber - (only just in the last couple of days found any mention of this on their website) …is what is causing my problems. Already ruined one set of brake pads and now I’ve wasted half a day’s work putting new pads on there using the same crap. I came across at least 4 other stories online from people - mostly Cavaliers but some others with similar metal pins inside rubber bushings/sleeves/boots or whatever you would like to call them - where the result was the same - the pins become absolutely stuck in place like they are super-glued in there …exactly the opposite of what you are trying to use the stuff for. I guess it reacts with the rubber and swells it or degrades it in such a way as to make it sticky.
All that means is that you don’t apply it to the rubber. The rubber seal is there to keep it in, it won’t hurt the rubber and it is not the cause of your problem.
One issue I’ve seen is with the bushing type (the ones where the mounting bolt goes through a hollow tube, which in turn goes through the caliper boss) is that the bushing will warp if over tightened. That reduces the clearances between the bushing and the caliper boss.
You have to completely clean out the caliper boss and the outside of the bushing. You should replace the rubber seals, they just aren’t that hard to get out or replace. Then use only a small amount of the grease. Too much grease can cause them to seize.
BTW, when they seize, the outer pad wears down to nothing and the inner pad show little to no sign of wear. If the inner pad wears out first, the problem is in the caliper piston.
