2003 V6 AWD 369k miles. Original owner and chief grease monkey.
osgood:
What, is this some sort of a test? Ha-ha.

I've replaced brakes a zillion times on my '03 and quite frankly I never noticed. I think my pins are the same for both. I don't know.....and somehow it probably does not matter. Good luck and thanks for posting.

Haya.... 😎
(Hayabusafalcon) translated means diving falcon-falcon. Goalie reference. Always out of position?!🏒

 

Ha! It's not a test. 😂 But you passed anyway! Thanks for the response. I think you're right that their position doesn't really matter in the end. I got 335K and 17 years out of my old Chevy so I just like to become very familiar with what I have at the time. Often to a fault. I did find a couple of people with the Lexus RX version of the 2003 Highlander with the same V6 engine saying the bushing pin goes in the top. Last thing I'll do is go to the local library and see if they still have factory service manuals like they used to when I was a young grease monkey. Other than that, I'll just do my routine inspections and keep an eye on it. I'll switch them in the unlikely event I have problems. Will definitely put new pins in next time (hopefully 75K more or so!).

 

According to the 2001 FSM and the 2005 FSM exploded views, it is on the bottom.

 

CR, thanks! I've seen similar scans of FSM that show that as well and why I was considering switching positions from how they were on mine. Interestingly, I found this scan (most likely for a 1999 Camry though so take that with a grain of salt) that specifically excludes the 1MZ-FE in a note and says to put it on the top side.

 

What is an FSM? Flying Spaghetti Monster? Full-Spectrum Microbiota? Finite State Machine? ????

 

Cripes.....OSGOOD-CONKLIN......you must be a Wings fan?

Dammed Sindy Crosby!

 

You can get on-line access to the FSM, wiring diagram, and TSB’s for $50 for a 5 year subscription at AlldataDIY. They recently raised the price. Mitchell1diy is probably about the same.

 

Hayabusafalcon, nope, not big into hockey, but I remember the name Chris Osgood. It's actually just an old time radio character reference. I'll think about getting a subscription to the sites CR mentioned at some point. Library only had the Chilton's and Mitchell's. Didn't have either the year or detail I needed. Thanks.

 

ossy:
What? not a big fan? Well that probably means you are not a Penguins fan either and have no idea why I added "Dammed Sindy (Sidney) Crosby". We don't like that player. Never have.
The reference was for 2009 game seven Stanley Cup finals Detroit vs Pittsburg. Both Chris Osgood and Ty Conklin were with the Wings at the time. (Conklin had been with the Penguins previously.) Those nasty Penguins beat the Wings 3-2 in OT to spoil the chance of a repeat Stanley Cup for the Wings. Shoot.

 

That's amazing that the random username I chose ended up being the last names of two NHL players! Very funny.

I noticed something else interesting about the caliper pin positions during my research.

On all the diagrams of Toyota rear wheel disc brakes I've seen, the slide pin with the bushing is shown as the lead pin. It's the lead pin because the rear brake assemblies (caliper & brackets) are usually mounted on the back of the rotors (facing the rear bumper) thus making the so-called 'bottom' pin be the lead pin. This is the exact opposite of the front (brake assembly mounted on front of rotor) where the lead pin is usually shown to be non-bushing slide pin.

For consistency, if you define the terms as leading and trailing pins (top and bottom are too relative to brake assembly mounting locations) as:
Leading Pin = the pin that a fixed imaginary point on a rotor first passes after during its normal forward rotation
Trailing Pin = the pin that a fixed imaginary point on a rotor last passes during its normal forward rotation
I don't drive very far in reverse so that's not worth discussing. 😂

 

A. It matters, one pin longer than the other.

B. I've had the situation where I used the wrong lubricant on the pin with the o-ring, and the o-ring swelled up, pin then jammed up in the hole.

 

Thanks for confirming the different pin lengths, Riick. It's subtle but definitely there. The non-bushing pin also has flats while the bushing pin is completely round. I wish I had measured the pin diameters and bore diameters while I had everything apart but was just wanting to be done since it was getting late. I do feel better about my decision to leave them in the leading pin positions where I found them in originally. It's a one owner vehicle with one brake job done by a Toyota dealer so that's only one opportunity for them to have been switched. If any place was most likely to be familiar with this and prevent it by either only servicing one pin at a time or at least putting them back correctly, I'd hope it would be there.

 

I'm with Haya, I don't think it matters. I try to keep mine in the right position, but sometimes I kick over all of my neatly lined up parts. I've even put that bushing pin in without the bushing. Never noticed a difference. Does anyone here know what is the purpose of that bushing and flat side?

 

The flats are to keep the pins from spinning when you tighten or loosen the mounting bolts. They catch on corresponding edges on the caliper body.

 

OE, thanks. I know what you are talking but I think Mgeorge was talking about the flats on the pin itself. The non-bushing pin has them. The bushing pin is perfectly round with no flats. You can just see them difference if you enlarge the pic on my original post. I can confirm that mine had the flats too as I had it in my hand.

 

Oh, gotcha.. The flats on the pins like that is usually to prevent hydraulic lock with the grease . Pressing a completely round pin into a (blind) close fitting hole... You need passageways for the lube to move around since it isn't compressible. But that wouldn't explain why there are only flats on one of them either.

And about your original question about "which one goes where?"... I've had mine apart a number of times, but I'm sorry I don't remember why they are different or which one goes where. None of my pics are detailed enough to tell.

 

Factory service manual. The manual that Toyota prints for use by professional technicians.

 

Thanks for your answer. I've since discovered that the slide pin with the rubber bushing goes on the bottom. This is how it's shown in the Chilton manual diagram. There are a few opinions as to the function of the bushing but many of them have to do with controlling that the caliper works correctly.

 

I’d rather use the Flying Spaghetti Monster.

 

I think the only way to definitively solve this mystery of the conflicting manual pictures and YouTube videos is to buy a new old stock, never driven or serviced 1st Generation 1MZ-FE V6 and also find a new old stock 4 cylinder where both have been in storage for ~20 years and never touched. Should be easy to find those nowadays...probably in someone's barn somewhere. 😂😂 Then disassemble the brakes on both. It would have to be filmed like Al Capone's vault opening was, of course. 😂 For an update, I've been driving my 2003 V6 FWD with the pin on the top for a few thousand miles since I started this thread with no discernible effects...yet. I just left it where I found it as the original owner had it exclusively serviced by a Toyota dealer (which admittedly doesn't mean much).

 

I always get a Chilton manual when I get a car. If you have one, look at the exploded view of the brake system. It will actually show which slide pin has the bushing.

 

I drive a Corolla Se 2018. Recently had pads and rotors replaced by an independent shop mechanic. Could be nerves and stresses since I asked him what grease he used for slider pins and got a vague answer “all we use are synthetics” Off course when I disassembled the left rear pins I found both pins had the rubber bushings (top and bottom) That is odd, unless he mixed them up from the right rear calliper. Before I remove rear right pins can anyone in this great forum point out the correct part for assembly?.

 

He mixed them up, maybe. I am not certain about the Corolla brake setup, but both my 2007 highlander and 2015 Lexus Rx350 has solid caliper slide pins on the top and slide pins with rubber on the bottom. I assume that is how Toyota does its calipers across the board on all models.

 

According to these 2005 FSM pages, slide pins with bushing, front and rear, go on the bottom.

Not sure about the logic behind it as the front brakes are in front of the strut tower and the rear brakes behind it, therefore it can't be due to first point of contact.

 

Great question, and one that’s easy to get wrong if you're not careful. On the 1993 Toyota Camry, the two caliper slide pins are indeed different, and their placement matters for proper brake function.
🔧 Pin Placement Details:

• Pin with the rubber bushing (also called a vibration dampener or sleeve):
  • This pin typically goes on the bottom of the caliper bracket on the passenger side, and on the top on the driver’s side.
  • The bushing helps absorb vibration and allows for smoother caliper movement under braking.
• Pin without the bushing (smooth pin):
  • Goes in the opposite position—top on passenger side, bottom on driver’s side.

🛠 Why the difference? Toyota designed it this way to help manage caliper movement and prevent uneven pad wear. The flat side on the pin helps guide the caliper’s motion and ensures it doesn’t bind.
✅ Tips for reassembly:

• Clean both pins thoroughly and apply high-temperature brake grease—but only the kind safe for rubber components.
• Make sure the pins slide freely once installed.
• If the rubber bushing looks swollen or cracked, it’s best to replace it. Using the wrong grease (like petroleum-based) can degrade it over time.

If you’re rebuilding both sides, it’s a good habit to remove and reinstall one pin at a time to avoid mix-ups.

(Found this via my Co-Pilot program in my own search of an answer, after looking at this and other chat threads and my Haynes Toyota Camry 92-95 All Models, that only had one photo Chapter 9-8 that was on the bottom, but without explanation. One YouTube video said to chalk one pin for each side and reassemble as originally found, but no explanation as to why. ) This Co-Pilot version make the most sense to me....and likely ok to switch the driver and passenger sides as long a one is up and the other down. Since this guidance says "Typically" goes on the bottom. Passenger side. "