So I was thinking that it would make greasing brake caliper guide pins easier, if you drilled a hole in the bracket, two of them, one into the bore of each guide pin. This would allow for for the pins to get more fully greased and would push all of the old grease out? Just pump grease into the bore until you see coming out of the boots. You could even pump grease into the bores for the guide pins in-between brake jobs without having to disassemble. Seems like a no brainer to me.
Is there any reason not to do this?
Note that I’m NOT talking about the bleeder screw. But adding in two Zerk fittings onto the bracket. This is for disc brake systems.
I have always recommended to.friends that have knee or hip replacement surgery that the surgeon install a replacement joint with a zerk fitting so the surgery won’t have to.be done over in a few years as long as the patient faithfully uses a grease gun
However, with brakes it is not necessary because the silicon grease can be applied when new pads are installed.
Look at @Triedaq 's response below. He’s absolutely correct. The brake pads will usually be replaced before the slides dry out, so one simply greased the slides at that time.
While intellectual curiosity is an admirable trait, you are very unlikely to out-engineer actual automotive engineers. As someone once said, a man’s got to know his limitations.
Original equipment still but wife tells me they don’t use a grease gun but a big needle. I think it is for the sake of the charge chart. Wouldn’t be able to charge for a quick grease job.
But yeah, I clean the slides and lube with the recommended silicone grease whenever they come out. Never had a problem and they are pretty well sealed. The grease comes in a tube and appears to be a lifetime supply.
I live in the rust belt. At the average of 15,000 miles a year, it would at least two years (hopefully) and probably even longer in-between brake pad jobs.
I use the Permatex silicone brake grease.
Which is orange in color. Whenever I do brakes and take out the guide pins, the grease is no longer orange but blackish in color. Sometimes they are even seized into the bracket, and I have to use pliers to pull them out. It can be a real pain. This suggests to me that the grease gets contaminated a bit in-between brake jobs. The boot is not clamped to the guide pins (for obvious reasons), which allows contamination.
I just find it really odd, when comparing greasing guide pins to greasing ball joints.
Guide pins are something that needs grease and a has boot that is not clamped, that you don’t need to apply grease every oil change or there would be no benefit in doing so. I understand if was a completely sealed system, it wouldn’t be necessary, but it’s not. It can also be a real pain to clean all the old grease out of the bore in the bracket for the guide pins.
It’s recommended for ball joints that are not sealed, to grease them every oil change if you have a zerk fitting, to push out the contaminated grease, until you see clean grease coming out. If it’s sealed then the ball joint should last a long time.
But I see what you mean, brake grease doesn’t come in a 14 oz cartridge typically, that you could easily get into a grease gun. So it’s a mute point.
If it’s any consolation, it’s not just a disc-brake guide pin problem. I had a problem w/the rear drum brakes on my Corolla a couple years ago, turned out one side wasn’t working correctly b/c the shoes were not sliding along the backing plate freely. This was the first time I had taken the rear brakes apart since the car was new, 27 years , nearly 200K miles. The original grease had just dried out.
I have no idea how long brake pads and shoes would actually last. I’m pretty bad to just change them all out at 100k miles with some life still left in them now. Drums in the rear, the shoes seem to wear less than the pads in rear disk setups. Maybe it’s because they get out of adjustment and wind up just not doing as much braking. Discs in the rear, the pads seem to wear more evenly, front vs rear. My wife’s old Camry had 208k when we got rid of it. I remember doing the front pads a couple of times. I can’t recall if I ever replaced the rear shoes. I do remember inspecting them and not changing them at one point, but I’m not sure if I ever changed them. I assume they were original. She bought the car used with relatively low miles before we were married. The first time I changed the front shoes was after our honeymoon at a cabin in the Smoky Mountains. Metal on metal sounds when coming down the mountain is no good! I changed the pads and rotors out first thing when we got back.
