Brake Pad Squealer Position?

[Tiny]

I should know this, however my recent experience has me confused. ¯\_(ツ)_/¯

Currently replacing a failed, pad damaged, front right, rotor(disc) on my 80 series Land Cruiser.
Now the pads were replaced by a mechanic (not me) when I purchased the vehicle, due to his determination that the pads were low on remaining material.
Not long after, another mechanic (not me) replaced a wheel bearing, as I had identified it as overheating & making noise. This was done 35,000km ago.
I should have done all the above myself, however I wasn't in a position to do so at the time & used a local trusted, by many, mechanic.

So fast forward to now, the brake pads have done ~60,000km, all other pads have not hit the squealer yet, even though this one pad had hit the metal backing plate, squealer broken off, never heard a noise until it hit metal to metal. Kudos to Toyota as the brakes were still working excellently.

So it failed & now I'm installing new rotor & pads, but I'm not sure if the squealer should be orientated to the leading or the trailing edge of pads. The old pads had one leading (inner) & one trailing (outer), the latter is the one that failed.

Have done some research & I get conflicting results, some say leading is best & some say trailing is best, for the squealer.

I can't blame the fail on the orientation, as the pad has obviously failed before the other pads were worn out.
I do use the vehicle in extreme conditions some times, so mud, stones & sticks can play a part in the failure.

The pads from Repco, I'm installing, have no orientation info, so should I care if the squealer is leading or trailing?

[Tiny]

Ok then, nobody.¯\_(ツ)_/¯
No one here does their own servicing anymore?
I miss you Godzilla.

So my experimentation with the old disc & a pad that had a squealer intact, was that it will squeal in either direction.

Note: my observation of the rear floating calipers, was that the squealer, placed on the leading edge of the old pads, was cemented into mud & had bent behind the pad friction surface, rendering them useless & 2 of the rear pads were beyond serviceable limit, not far off causing a disc failure.

Hope that helps someone else.

[wotnot]

top of caliper

[Tiny]

top of caliper

Thanks for your opinion, however, unfortunately that would give conflicting results due to forward or rear mounted calipers.

Eg; the Landcruiser has rear mounted calipers on the front, so that would put the squealer on the trailing edge & with forward mounted calipers on the rear, would put the squealer on the leading edge.¯\_(ツ)_/¯

[wotnot]

Not opinion, what I saw in the parts diagram ... image below is rear.... fronts differ depending on exact model

[Tiny]

Ok so that's the left rear in orientation, which puts the squealer on the leading edge.

note; that the squealer on the rear is a different type to the fronts & I placed it back in the top on the leading edge as shown, as that's how they came out & on reassembly it would be difficult to put them on the opposite end of the pad, as the pad wouldn't fit back into the caliper like that.

With the fronts I went 50/50 like the previous mechanic did.

[Tiny]

With the fronts I went 50/50 like the previous mechanic did.

Previous mechanic Wrong.
So I just serviced the Wife's Hilux & replaced the front pads as they have done 140,000km.
Believe it or not, they still had over 30% remaining before squealer contact.
Anyway, this car has been owned since new, never had pads changed before, so the original Toyota pad fitment for the front as installed by Toyota, is squealer placed on leading edge on all 4 pads. That orientates to the bottom of the rear mounted front caliper. Previous mechanic got it wrong.
So as the old LC had only been driven down the paddock & back since new pad & rotor replacement, I changed the pads to orientate as per Toyota design.

In conclusion the squealer should be placed on the leading edge of the pad, when forward vehicle movement is taken into perspective, regardless of brake caliper orientation.
Using a top or bottom of caliper position is ambiguous with the different caliper mounting positions.

Also in hindsight, I probably should have used Genuine Pads, as they are about the same price as the Repco & Bendix replacements I've used & my suspicion is that the Genuine will outlast the aftermarket by a long way.
Do they have the same braking feel & power? Yet to be tested, so I 'll draw my conclusion after I've driven a few hundred Km's.
All reviews on 4WD forums suggest the after market pads out preform in braking feel & ability. We'll see.

[Godzilla]

Hi Tiny, sitting here at work taking a break and thought to myself i haven't been on Austech for years and years so here i am.

What im about to write is very broad, however there are many exceptions.

Those metal wear indicators are handled in different ways (strange ways) depending on the manufacturer of the car and in many cases the aftermarket pad manufacturer.

In one sided piston/s caliper applications they are usually fitted inboard when only 1 or 2 are supplied, that is if you have 2 pads with it usually both go inboard on both side. Some pads have all 4 with wear indicators, some just 2, just 1 is also common.

Many pad manufacturers make just 1 pad with a wear indicator, again, inboard, doesn't matter which side.

The attitude is both sides should be wearing evenly so 1 side is enough, always inboard on single piston calipers.

Thats because the inboard pad contacts first, so therefore it should see the most wear, obviously this does not take into account that your sliders could be sticking and your outer pads are dragging and therefore wearing faster, everything is assumed to be in top condition and if not the finger gets pointed to the vehicle owner (welcome to warranty rejection 101)

Position of the wear shim is usually on the leading edge of the pad, that is the disc meets the wear indicator first, not as the disc leaves the pads. Ive seen factory brakes either way but the majority as ive stated, does it matter, not really, its just there to make a metal to metal sound.

Calipers with pistons either side (inner and outer pistons), in this case both sides wear evenly (hopefully), really does not matter which side the wear indicator goes on (inner or outer), hopefully all 4 have wear indicators, again i usually fit the wear incicator the the rotor sees it first when passing the pad.

Also on a side note, put some ceramic brake paste (i use copper grease when none at hand) on all metal to metal contact points (obviously not on the discs or pad friction material). Look at the pads removed, note where the pistons made contact, run some paste on the new pads in the exact some spots, also look at the very leading and trailing edge of the backing plate, do the same there too to keep brake noise in check.

Most brake noise is the pad vibrating in the mount, rubbing dry metal to metal.

Hope that helps you.

Im now semi retired, my son has taken over the running of VMAX Brakes, i just open up and hang around all day playing here and overlook/assist him running the show, its like a man cave at the factory so im here almost 7 days a week till late at night playing with my toys.

Still have my GTR, its currently in Sydney at Powertune Australia getting some final tweaks before its final tune after some major upgrades.

I got into Autocross 2 years ago for fun on dirt after buying a WRX and joining Bendigo car club, first year managed a third outright, second year second outright, this year ive moved onto the Victorian Rally championship at club level, 2 weeks ago i did my first full rally as an old fart at Mitta Mountain, took it easy and managed a 10th outright at club level and second in class (turbo 4wd).

In under 2 weeks time im at the ADA River rally so late nights at work prepping the car now.

[Tiny]

Thanks muchly for your insights Godzilla.
Glad to hear you're having a good time after many years of running your own business. Early retirement (even semi) is awesome, as you are still able to do the extreme toy stuff.
I'm still riding a motorcycle & doing the odd track day at Symmons plains.