Break pads and disc replacement
 

Hello all,

As per the subject, I am going to replace the disc and pads on Friday.
Do you know what size of alan key I need to unscrew 2 bolts that hold the calliper to the hub arm? Those bolts under a plastic cover

I am asking as I would like to buy it if I don't have already this prior I start work.

If I miss any tool/key I have all the shops far away from me and without a car I will have a problem.

Thanks in advance

I am pretty certain it's bigger than most caliper hex bolts, I had to dismantle my brakes recently due to lack of use and seized pads, and I had the same issue.

The front hex key is at least 10mm, possibly even bigger, my guess is 11mm as my 10 was just a bit too loose inside it

The rears are smaller hex key, around 8mm

Thank you it means I have to buy hex 11mm as I don't have it at all. Massive thank u

Did you manage to use 10mm to unscrew it? I see hard to find 11mm. 10 or 12 mm only

Yes, 11mm. I bought a pair of 11mm hex sockets on Amazon, one long, one short for about a fiver. Did the job.

Just watch if you’re doing the discs too. The caliper bolts are bastard tight and loctite too. I needed a spanner on a spanner to break them free as I didn’t have the right socket for those either (can’t remember what size, but I did a thread on replacing all discs and pads a couple of months ago and it will be in there).

Yes. I found your post

Will that work for me? I am not sure.

11mm key

It's it 11mm hex?

That'll do yep, 11mm

I knew it was bigger than a 10, I can remember buying one to do it from a local motor factors so posted the above advice from memory sorry 😁

Assuming you've got alloy wheels, on final reassembly put a smear of copper grease between the contact points of the wheel the disc and the hub collar to prevent future corrosion between the steel and alloy. This will make the wheels much easier to remove in the future.

You are very helpful. Thank you

Will LIQUI MOLY Brake Anti-Squeal | 100 g | Paste | do the job too?
I have ceramic grease no idea if i got copper one

Can't answer I'm afraid. The problem is caused by dissimilar metals (aluminium alloy and steel) in the presence of water, especially salty water. The copper grease helps aleviate the corrosion. I've used it for years and always been able to remove the wheels when needed. Without it on e.g. a new 2nd hand car I've had to resort to loosening the wheel bolts a little and driving slowly round the block so that the lateral forces when turning breaks the wheels loose.
Google what you've got and see if it's suitable.

Ceramic grease is preferable and modern, copper grease is conductive and can cause abs sensor faults.

I never smear on the rear of the pads, only on friction / movement joints against the carrier, as the OEM pads have a double sided sticky pad that sticks the pad to the caliper already (or a non sticky pad on other brands)and the metal clip does the same for the one that faces against the piston.

I am under the impression that it's also bad practice to use any copper slip on the face of the wheel hub/disc where the wheel mounts against because it can compact and cause wheel imbalances. Best just brush any muck away and leave it all rusty coloured against the wheel

Thank you.

First time I have heard about putting grease between the wheel and hub. I could see that Volvo garage didn't do this when new tyres were installed.

Also, I never saw before to put any Brake Anti-Squeal paste but I have watched plenty of videos and this paste is used.

I'm only talking about a smear, not a tin full! You're far more likely to get wheel imbalances after you or someone else who can't get the wheel off a year down the road, because it's corroded around the hub flange in particular, takes his 2kg club hammer out and tries to knock it off.

Been maintaining my own cars now for well over 50yrs and using copper grease ever since I've had cars with alloy wheels and it's served me well. Others can do what they choose.

I always put a little copper grease on the back of the wheel, had too many wheels bond themselves to the disk.

What you must never do is put a layer of the stuff on the hub before fitting a new disk, it used to be "the norm" but modern braking systems have so little lateral movement in them that the slightest bit there tends to cause disk runout, which turns into uneven wear - causing a pulsing at the pedal.

Please find this video
https://www.youtube.com/watch?v=jFsx5DuWARI jump to 6min 46sec.
He is putting the paste exactly where you say no.
I am confused :D

He put a small brush full on the hub... he didn't put the tub on.

All you need is a small smear of it.

I've always used copper grease on the hub, just a small amount. Never had an issue getting the wheel off or brake disc runout.

Had a garage do that on my last v60, caused no end of run out issues, which went when I fitted the disks myself with the hub clean after getting advice from the brake disk manufacturer who stated that it must never be done as even the smallest amount can cause issues. Then had a seized calliper which caused warping but that's a different story.

It apparently wasn't an issue with the older calliper design where the whole calliper moves back and forth on sliders, but the issue occurs with the newer fixed type where only the pads and piston move as there's less movement possible before the run out is felt at the pedal / wheel.

Thanks for the information. Also, I have read/watched about this and they told me I should not put anything between the disc and the hub.

I will still use for brake pads Anti-Squeal paste and ceramic grease for caliper pins.

I hope the change will go smoothly tomorrow. weather dependant

Due to the thread lock, I needed to buy a blow torch this year (Screwfix) to remove the caliper carriers.
I would suggest buying one before you start (you can always return it), unless you have access to another vehicle should you need to buy one.

Hey,
I did front brakes yesterday so far so good.

Tomorrow I am planning to do rear.
I have checked rear brakes and compared parts.
The question is what for that metal things are? I am asking as I got exactly the same brake pads that i have installed right now and there is no those metal inserts.

Those are referred to as "brake hardware". When you take your old pads out, you'll see these metal clips (they'll be all likely full of dirt) clipped into indents of the brake caliper mounting carrier. Take those old clips off and fit the new ones. If you don't want to do that, make sure you clean the old ones well for smooth brake operation. Also, make sure the part of the clip where the pad sits into is lubricated.

I'm not sure why the fronts didn't have new brake hardware. Good quality pads usually come with new clips for the front and rear. Its possible that the front has a different design to the rear, i.e. there may be no clips on the front, but there might be on the back. I've seen that before.

@Kev0607. I recently did the (old shape) V60 front and back.

The back pads had these clips which were fitted as you describe. The front didn't. So yes it is often the case. Just depends how the different calipers are designed.

Hello all,

Quick info for you if you are looking to change brakes by yourself in V90 D4 MY20.

After you get the correct parts from any shop you normally use make sure that you have too.

• T30 Torx bit for Disc screw. 10Nm to screw it back.
• 7mm hex bit drive 3/8" for 2 caliper slide screws. Same size front and rear. 57Nm force to screw it back.
• 18mm Socket 1/2" drive for Front caliper bracket. 200Nm.
• 15mm socket 1/2" drive for rear caliper bracket. 120Nm.
• Caliper push tool.
• 9V battery for winding your rear brakes.

I found out that my car get DTC on ABS after I winded rear brakes.

• C20071B - General electrical failure of the right motor
• B111167 - Electric parking break enabled. incorrect signal after the event.

There were no driver assist available like speed limit or pilot assist.
Since DTC removed all is great. Have this in mind when replacing brakes.

One more thing to say there is no vibration during driving or under braking, I would say the vibrations have gone that I had previously when I was going with speed between 80-90mph.