Hi All, I have 2008 3.6, and just lost a rear brake pad, the piston popped followed by all fluid and zero brakes. Luckily in supermarket car park and no damage, apart from to nerves. There was a little warning with soft pedal then none, had this been on the road the consequences could have very nasty.

Has anyone had or heard of this happening before?

The remaining pad is 12mm thick, 6mm steel and 6mm pad.

I’m concerned by the gap in the carrier, see photo it’s nearly 10mm on the outside and only 2mm on the inside. So as soon as a pad gets to 10mm it will fall through the gap.
Is this right?

I have warning sensor on this side which didn’t activate.

Thanks all

Has the bearing moved?
The sensor is a wear sensor so it must still be intact for the warning not to have activated.

Not that I can tell, no wobble in hub, gap from guard small and hand brake works fine.
I will add it was the drivers side that fell off.
Checking passenger side and it’s the same, large gap between the carrier and disk at the outboard side, small inboard.

Are the calliper sliders siezed?

This needs a picture please, because unless the caliper carrier has snapped / broken, as I see it, it's impossible to lose a rear pad - unless the wrong pads have been fitted.

If the correct pads are fitted, they can't get out in any direction due to the design of the caliper and caliper carrier itself. The only way to lose a pad would be if the caliper has flipped open after losing a slide bolt, but then that'd be impossible with the wheel on, and you'd have seen it!

So no, the other pad can't fall out, unless as I say, it's fitted with the wrong pads?

Are you sure the pad is missing and not just worn down to its backplate? That can happen if the slide pins are seized. If not, then the pad can't have been installed in the first place. Perhaps someone was struggling with seized caliper slide pins and only installed one pad on the piston side of the caliper!

Also, I really can't see how the piston itself can pop out if one pad is in there with 6mm of meat? Unless someone's really butchered your back brakes. In fact, it shouldn't pop out at all so long as there's at least two brake pad backplate thicknesses in there (i.e. if both pads were down to their backplates, the piston should still never be able to pop out). This is basic automotive design allowing for clowns who run their pads down to nothing, yet still not lose all their braking. Well, half technically, due to split braking system.. but you get my point. 1992 RR Classic 3.9 efi Vogue
2014 Disco 4 HSE
===================
Both my fatties now gone...
Previous: 2011 L322 4.4 TDV8 Vogue SE /// 2002 L322 4.4 V8 HSE /// 2009 Discovery 3 2.7 TDV6 XS /// 2004 Defender 90 TD5 /// 1993 110 V8 Snatch Landrover /// 2005 Discovery 3 2.7 TDV6 SE (Aus) /// 1990 110 Isuzu 3.9 County (Aus) /// 1976 Series III Trayback (Aus)

Leigh4571 wrote:

followed by all fluid and zero brakes.

Here are the OP’s photos.

I was going to suggest incorrect discs have been fitted, but they’ve obviously been fitted for a good while before this issue has occurred, so perhaps not. The disc not being located centrally between the carrier does look suspicious though.

As others have said, I can’t see how a piston would fall right out even with zero friction material remaining on the pads. Do you mean it pushed beyond the end of the bore or literally fell out?

Click image to enlarge

Click image to enlarge

Have you got the brake pad that fell off, if so is there any pad material on it.

How can the pad 'fall off' when there is a caliper attached???? 2012 TDV8 Vogue (L322)

I don't have the missing pad but all the rest are 6mm give or take.

No the pins are not seized.

Yes the piston came out of of the cylinder, just past the seal followed by all the oil.

Exactly! how can it loose a pad??

I have had a car in the past loose the wearing surface, made a nasty noise metal on metal but the car stopped.
This RR just dropping pads out when they get to 10mm is terrifying, the passenger side is the same with a 10mm gap from carrier to disk.

Is it possible it's got the wrong disks on?

According to my parts guy;
A rear disc ( 3.6 TDV8 ) LR031844 is vented !!!!
Up to 2005 it was SDB200211 and solid

So my 2008 should have vented on the rear like the photo, this make sense?

That there is your problem then. You've solved this yourself.

The reduced width of an unvented rear disc has allowed the piston to travel beyond its cylinder in the caliper leading to it popping out.

Not sure how you've lost a pad, assume it was the outer one? But it must be related to the unvented disc being fitted, allowing the outside pad to get through the gap, or it also had the wrong rear pads fitted as well! The uneven gap is due to non-vented disc being fitted of course!

As others have noted, the caliper carrier is at an odd angle *EDIT* ---> The caliper carrier should be parallel to the disc face. Don't know if it's just the picture making it look at an odd angle. The caliper itself should move smoothly & evenly on it's two slide pins to allow for pad wear.


I'd be a bit worried as to what else has been bodged on that car? I'd have it checked over, or at least 'spanner over' it all to ensure everything is tight in the commonly replaced items (front suspension arms, track rod ends, rear upper and lower hub knuckles, etc. Also caliper and carrier bolts front & rear).

Jon 1992 RR Classic 3.9 efi Vogue
2014 Disco 4 HSE
===================
Both my fatties now gone...
Previous: 2011 L322 4.4 TDV8 Vogue SE /// 2002 L322 4.4 V8 HSE /// 2009 Discovery 3 2.7 TDV6 XS /// 2004 Defender 90 TD5 /// 1993 110 V8 Snatch Landrover /// 2005 Discovery 3 2.7 TDV6 SE (Aus) /// 1990 110 Isuzu 3.9 County (Aus) /// 1976 Series III Trayback (Aus)

Last edited by D3Jon on 26th Mar 2024 12:34pm. Edited 3 times in total

I ordered some rear discs from auto doc, correct part number etc but they sent the solid discs which are smaller too.

So I guess it’s possible you have the wrong discs on for the car, although not sure if you could get them to go on?

………. “If it ain’t broke, don’t fix it” -where’s the fun in that?

Last edited by Gremlin500 on 18th Apr 2024 10:12pm. Edited 1 time in total

Hi All,
So new vented disks and pads on the way.

Yes the carrier is level with the disk. Here's a couple pics with the remaining pad in the carrier, this pad is 12mm total, 6mm steel & 6mm pad.
As you can see a bit of effort or 1mm off and it's gone down the gap, out of the carrier and bouncing down the road.

Click image to enlarge

Click image to enlarge