doubledeala

So this is my second time having seized sliding pins on the TL.
First time I found that one of the FR pins was seized, I refinished it and put it back in--I just found out that I could buy a new set for 10 bucks so I would not recommend refinishing unless you're really short on cash.
Ever since repairing the seized pin, I haven't had the shimmy come back in over a year.

Just yesterday, I replaced the rear brakes because they started squealing and I find that the inner pads were worn way down and uneven. The culprit was one of the sliding pins on each side. Sliding boots were perfectly fine so I couldn't figure out why it would get seized on it's own.

After looking at three seized pins, I saw a failure trend. I don't know if you guys know this, but each caliper has different sliding pins (unless mine are not oem).
One pin is 100% round, one pin has 3 flat sides. All three seized pins are the ones with the 3 flat sides. The grease gets cooked in the void between the flat side and the cylinder walls--thus seizing them. When I pulled the pins out, they had black gunk baked onto the pins and more stuff in the hole.

Attached are pictures, I tried to take ones showing the flat side but have at it.

01tl4tl

good catch!

We should be cleaning and relube these CRITICAL brake parts with pad change,, at the least
but with pads going 50kmiles/several years, its probably a good idea to do the brake fluid flush and complete caliper cleaning and lube all parts-sliders-pins, pad backs etc
every year, or 2 years
If you live in harsh weather conditions, earlier is better ..as shown above

I wonder if the flat ones used to be round?
any pin gurus or acura parts counter guys know for certain?
Since I dont know, it must be time to service my brakes- though I run legend calipers in front so who knows if identical on the pins

Note on rear pad wear, MANY pad makers used the backing plate for the RL and sell as for us.
BUT its the totally wrong part for the TL!!

the WRONG rear brakes INNER pad has a 3rd/middle raised tab on top center,
that hits the piston before the rest of the pad and makes it press the rotor at an angle,
grinding pad down crooked ,, and not having full pad contact = lower brake effectiveness

the correct pads have a tab at one end holding the `low pad noise maker device`,
there may be an empty one at opposite end or no others- thats fine
just `no center tab` is the key

Easy ck- look under car at rear rotor inner side
half of its width rusty-- and half shiny = wrong pads problem

doubledeala

Very true 01tl, its so easy to lube those parts that it should be part of the brake pad change routine.
I don't think the pins used to be perfectly round based on the uniformity of the flat sides and that 3/4 corners have the flat pins. I'll be replacing the front flat sliding pins on my next brake job.

Never had that RL pad problem though. Good to know.

shamal

My TL has one each of the pins, and the manual shows an A pin and a B pin. My outer pads were worn much more than the inners next to the piston, and I assumed it was because the pads hung up on the metal brackets. The rubber boots were in excellent condition, no leaks into the pin sockets. My pins were well lubed and not stuck that I could tell. Nonetheless I removed and cleaned everything, starting with new grease in the pin reservoirs. I too wondered why two different pins were used, I did not find further mention of this. Anyone know anything further? The metal brackets looked a bit too old, and i wondered if the last guy who did the brakes did not change out the brackets and springs that come with the brake pads?

01tl4tl

very few places replace or even bother to clean and regrease the slider plates/spring plates where the main pad to bracket motion is taking place, or the slider pins inside the boots that allow the caliper to pull across the bracket
Most brake pad makers sell the spring parts kit separate, so its not purchased~
Many DIYrs dont know how to properly grease their brakes!
We see questions on that over and over, Simple answer- look at the wear marks on old parts! Thats where they move and need grease

When installed and torqued correctly, with brakes pumped up to operating position, but at rest.
You should be able to move the caliper slightly and see the pads moving too

Shamal
Good job using search for info- no need to dig up threads last posted to 4-5 years ago.
By now most info has made it into a diy- ck those out,
`New OFFICIAL 2nd gen` blah-blah...near top of thread list after you get to
main 2nd genTL page on here

dpalmer

I'm servicing front calipers on my 04 TL and noticed the same difference on the caliper pins. I had one smooth pin and one pin with flats in each front caliper. The flats look stamped/forged into the shaft and is too uniform to be wear or any defect. When I pulled them out I didn't take notice of which location I pulled them out of because I assumed that they were identical pins. the ones with the flats even seem to have a different plating than the smooth ones. the ones with the flats seem to have a zinc plate with yellow chromate and the smooth ones are darker and seem to be a little smoother, almost like they have a coating to reduce friction (see attached pic). I'm wondering if the one with the flats are supposed to be installed in a specific location in the caliper. Does anyone know an answer to this?

SuperGreg

A shop *should* relube everything when they do a brake job, but that's why I do my own work, to make sure it gets done correctly. I remove, clean, and relube everything as appropriate every time I do a brake job. Make sure to use proper brake grease.

SuperGreg

I just checked the shop manual, for the 2nd Gen TL it says the front pins are identical, for the rear it labels them Pin A and Pin B:



Looks like the round one goes on the bottom.

01tl4tl

maybe the round one is to allow smoother caliper motion on the sliders/pins?

When you apply the brake there is a forward rotational motion of the caliper-
and brake pads move within their confines...hence the springy clips they fit into