Brake Caliper Pins: One Has 3 Flats, Other One No Flats. Where Do They Go?

[Peteco]

Decided to replace the caliper pins on my 2006 Chevrolet Express 3500 van. Removed the caliper pins not paying attention to them. Went to put in the new pins and noticed one pin has 3 flat sections about 1/8-inch wide running along the length. The other pins has no flat sections.

Could find nothing in my GM Service Manual nor on an extensive google search. Did find that some Hondas have these, with differing views on where they go. Most often recommended is the cylinder pin (with no flats) goes in the hole near the leading edge of the pad. That is the pin hole where the rotor enters the pad as it is rotating forward. This is the top pin location when the caliper is on the front-side of the rotor, and the bottom pin location when the caliper is on the rearward side of the rotor.

So does anyone know where they should go on a GM vehicle, and why?

 

[Hall]

Haha ! I saw your reference to Honda pins and had to laugh.... I've dealt with those many times and there doesn't appear to be much consistency. I don't have service manuals but Honda's parts diagrams are actually detailed enough that they show different pins on the leading edge vs trailing edge, as well as showing the rubber boot.

Sorry can't help though.... In the end, I don't think it's mission-critical. The rubber boot or flats are supposedly for noise-dampening so if it sounds okay when you put things back together, don't lose sleep over it.

 

[Rand]

pull other side and check is best way.

Also why you never work on both sides at the same time.(ie tear both sides down at same time)

 

[benjy]

not paying attention as i remove parts as i should i see similar issues with my 2011 fronty SV. being preowned dont help!! had uneven pad wear + of course pins did NOT move freely as they should.

 

[brages]

Beveled pin on top is what I found in an internet search.

Rubber bushing pin goes on the bottom, if you have one.

 

[D60]

Best I could tell on Fords like '04-14 F150: concensus seems to be it doesn't matter.

 

[dubber09]

What @brages said. Straight pin should be the top one.

 

[Dadillac]

I have been battling this dilemma for many years. About 6 years ago I changed the front brakes on my mother in laws Kia Sorrento. She was the original owner and this was the first brake job. Calipers had the straight pin / bushing pin combination. One side had the larger straight pin on the top. he other side had the straight pin on the bottom. So from that day forward I declared that it does not matter the pin placement.

Don

 

[D60]

I have been battling this dilemma for many years. About 6 years ago I changed the front brakes on my mother in laws Kia Sorrento. She was the original owner and this was the first brake job. Calipers had the straight pin / bushing pin combination. One side had the larger straight pin on the top. he other side had the straight pin on the bottom. So from that day forward I declared that it does not matter the pin placement.

Don

This also seems to be what Ford owners report. One guy will say he took his apart and it was one way, the other guy will report the opposite -- and both had brakes that were fine for tens of thousands of miles.

Now, YES, if the FSM speaks up, follow that. But if there's no mention.....not sure it matters.

 

[dumkid]

I put the rubber ringed pin on the trailing edge.

 

[Peteco]

OK, here are two links that have discussion on some Hondas and a page from the service manual (Sorry I don’t know how to put pictures in here, thus the links).

This one shows the caliper at the front of the rotor. The cylinder pin (with no flats) is in the top hole, which is at the leading position where the rotor enters the pad as the vehicle is moving forward.

https://bobistheoilguy.com/forums/t...ord-lx-2-3-caliper-guide-pin-location.297855/
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This one shows the caliper at the rear of the rotor. The cylinder pin (with no flats) is in the bottom hole, which is at the leading position where the rotor enters the pad as the vehicle is moving forward.

https://www.crvownersclub.com/threads/brake-caliper-guide-pins-on-honda-vehicles.93281/

So is this how it should be for all vehicles that have pins with flats, or just Hondas??? I’m assuming this is correct for my GM vehicle. Sure would be nice to have something more definitive.

 

[Hall]

So is this how it should be for all vehicles that have pins with flats, or just Hondas??? I’m assuming this is correct for my GM vehicle. Sure would be nice to have something more definitive.

It certainly could be a standard. Remember too that a lot of brake components are effectively purchased parts or a 3rd-party manufacturer's design. Honda uses NISIN, Ford uses ATE (and others), and so on so the basic brake design will be similar.