I have a 2012 Focus Mk3 1.6 TDCi and have been having this issue with the N/S/F brake since I bought the car earlier this year.

When braking, the steering wheel wobbles. When not braking, I can hear a squeak coming from the N/S/F that stops when I brake. The wheel is also slightly warmer, but by very little.

 

I have:

- Replaced caliper

- Rebuilt original caliper

- Replaced slider bolts and boots

- Sanded the hub surface, carrier, and greased all main contact areas of the pad wings

- Replaced tyres and had wheels balanced

- Replaced the discs and pads three times in between all of the above.

Replacing the discs solves the issue until a few weeks of driving brings the problem back.

I know what the problem is, I just don't know the cause. The problem is that the disc isn't sitting true, causing the pads to move back and fourth, squeaking them as they do and causing a wobble when braking. It's the cause I'm struggling with...

I narrowed it down to a bad wheel bearing; this could definitely be the cause. I've booked it into my local garage Wednesday as I've got a new bearing in the boot of the car for them to fit, but now I'm reading more and more about how the driveshaft could also be the cause.

If it's the driveshaft then I can replace this myself, but I'd need a garage to do the wheel bearing if not. At this stage I'm very much up for them to replace both and to get it over with, but am so worried of the issue coming back.

Can anyone shed some light on this? I don't get any wobble when not braking, only a light squeak from the brake on every rotation.

Many thanks.

It's hard to diagnose a wheel bearing without removing the brake pads,  which are in such close contact with the disk that they prevent any movement from a normal worn bearing test. You can use a mechanic's stethoscope to listen out for worn bearing noise, comparing each wheel.. but, hey, it's booked in now so wait and see. I can't see a worn UJ causing the wobble tho'

 

If the disc is not sitting true it will defo wobble as that is part of the rotation of your wheel as joined to the hub so your wheel won't be bolted on 100% flat either. I wouldn't drive it like that. When they do the wheel bearing the drive shaft has to come out anyway so get them to inspect the behind parts whilst doing it. Did you hear any extra noise when going around roundabouts? Although deisel is noisier it may be harder to detect the extra sound that wheel bearings can make. When I got mines done from stef on here he spun the wheel hard whilst it was high up on ramps and it was obvious it was the bearing on the driver side. 

Have you put a DTI on the disc to check for runout? If there is runout that exceeds the specifications and the mating faces of the disc and hub are perfectly clean I would use the DTI to check for runout on the hub face and also play in the bearing. I wonder if the wheel has been heavily kerbed in the past and distorted the hub.

My guess would be bent hub tbh, is the hub integral with the bearing on these?  Can't remember (I must be slipping!) but I'd change both if not. 

Driveshaft can't change the angle of the wheel/hub so although it can cause a wobble through the car it won't cause your squealy pad issues.

Hubs can get bent by people using different torque settings on the nuts.  People sometimes leave lockers a bit loose if they're starting to round but it's not a good idea.

The Focus MK3 uses a GEN2 wheel bearing.

On a GEN2 wheel bearing the wheel hub is an integral part of the bearing assembly. GEN2 wheel hubs need to be removed/installed using special tools. The GEN2 bearings that Ford uses have different dimensions from the GEN2 bearings that are used by most other car manufacturers. Most universal GEN2 removal/installer kits do not contain the correct size tools for the Ford GEN2 bearings.

These wheel hubs can easily become warped. For example by combining different types of wheel nuts (old design wheel nuts with new global wheel nuts) or by failing to apply the correct tightening torque to the wheel nuts. Whether the hubs are warped or not can easily be determined by measuring the runout of the hubs.

Measuring the runout of the wheel hubs should always be performed if the brake discs are warped. Especially when the brake discs have been replaced before for the exact same reason. Just replacing the brake discs 3 times does not make any sense at all.

36 minutes ago, JW1982 said:

The Focus MK3 uses a GEN2 wheel bearing.

On a GEN2 wheel bearing the wheel hub is an integral part of the bearing assembly.

These wheel hubs can easily become warped. For example by combining different types of wheel nuts (old design wheel nuts with new global wheel nuts) or by failing to apply the correct tightening torque to the wheel nuts. Whether the hubs are warped or not can easily be determined by measuring the runout of the hubs.

Measuring the runout of the wheel hubs should always be performed if the brake discs are warped. Especially when the brake discs have been replaced before for the exact same reason. Just replacing the brake discs 3 times does not make any sense at all.

Some great information, thanks for that. Thankfully replacing that will be a 2 in 1 success, as I'd be replacing the hub and the bearing at the same time. It looks like I've purchased the wrong bearing from EuroCarParts, the bearing I've bought is just the bearing and not the hub.

I've found this Ridex bearing for £32, or this FA G SKF bearing for £86. That's quite a price difference. EuroCarParts don't seem to sell the bearing, so is there anywhere else you'd recommend?

Ah. Regarding changing the discs three times, I didn't change them for the same reasons. I'll explain:

When I bought the car, it was sat for months due to covid in the forecourt (along with a dead battery), and the disc had clear marks that didn't go away after driving, which I thought was causing the wobble and squeaks. I replaced the two front discs/pads and the wobble went away, and that was that. When the wobble came back after a week or so (and a 3.5h drive), I found the marks were nothing to do with the wobble, and in fact the caliper was binding (it was very, very hot), so I replaced the caliper with a new one along with a second fresh disc (though no need to replace the other side as it was already new, which meant I had a spare). Problem sorted (or so I thought), but the new caliper was so poorly made that it actually sat on an angle, causing the disc to wear unevenly. There was no wobble with the new caliper though, just the squeaking, so I decided to rebuild the original caliper with a new piston and seals, and placed that spare disc on so that it was all fresh and new. Rebuilding the original caliper and using the new spare disc had solved all of the issues, and the disc was now starting to wear correctly... but as of a week ago the wobble/squeak is back, hence my decision to start this thread. That's pretty much how I came to replace the disc three times, it wasn't just replacing it for the sake of it. Though looking back you're absolutely right, why I didn't get the runout checked before changing it I'll never know. I just assumed it was the caliper, but lesson learned.

Thanks for the help everyone, really appreciate it. Are we in some sort of agreement that it's most likely not the driveshaft and is most likely the hub/bearing that needs replacing?

I personally prefer SKF wheel hubs. The original Ford wheel hubs are also produced by SKF. 

Worn driveshafts usually result in different symptoms. All worn driveshafts that I replaced resulted in severe vibrations (especially under load). 

3 minutes ago, JW1982 said:

I personally prefer SKF wheel hubs. The original Ford wheel hubs are also produced by SKF. 

Worn driveshafts usually result in different symptoms. All worn driveshafts that I replaced resulted in severe vibrations (especially under load). 

Good to know, I'll go for the SKF. I've found that the EuroCarParts Ebay store has the item, but it's not on their website. I'll give them a call to see if they can order it in store for me to collect as I live close to an outlet. 

On a side note, what headlights are those? They're fantastic! I'd love to know where you bought them from?

The headlights I have are really rare. These headlights are called Sky-Wing headlights and were produced by a Taiwanese manufacturer called Eagle-Eyes. The white beam inside these headlights is illuminated by LED. These headlights were based on the USA headlights (side reflector).

Unfortunately these Sky-Wing headlights were only available for LHD traffic. RHD versions were initially available on demand but required a minimum order of 50 sets. The production of these headlights stopped Years ago. Some German websites still offer the silver LHD version but prices went up to approximately €700,- .

4 minutes ago, JW1982 said:

The headlights I have are really rare. These headlights are called Sky-Wing headlights and were produced by a Taiwanese manufacturer called Eagle-Eyes. The white beam inside these headlights is illuminated by LED. These headlights were based on the USA headlights (side reflector).

Unfortunately these Sky-Wing headlights were only available for LHD traffic. RHD versions were initially available on demand but required a minimum order of 50 sets. The production of these headlights stopped Years ago. Some German websites still offer the silver LHD version but prices went up to approximately €700,- .

That's a shame, I'm planning on splitting my headlights to install projector lenses so that I can use xenon bulbs; I had done it to my 986 Boxster S with huge success, and have heard it's been done on these. £50 for the projector lenses, £50 for the xenon bulbs, a cheap and powerful upgrade overall.

Anyway, I digress; thanks very much for the help on the hub. I'll update everyone when I get it replaced. I'm just hoping I won't have to replace the disc afterwards to a new one, and that the wobble is simply being caused by the hub/bearing, and not because it's warped the disc. Time will tell.

Just to give everyone an update, this Gen 2 bearing and flange that I've bought was the wrong one.

 

The garage has told me it in fact it has the separate bearing and flange, not the all-in-one, so they couldn't fit the new one when they removed the old bearing. It's no bother, they've sourced the correct parts and I'll get a refund on the gen 2 part. The new parts are a tad more expensive though; the bearing is only £30, but the flange is £120. That's the cheapest they could find, as Ford wanted over £250.

They were a little stumped at what it was. They could see that the brake had a wobble under testing, but the bearing showed no signs of failure, no noise and no play. I'd told them everything I've done to the brakes and they confirmed they couldn't see any issue with the brakes. We were in agreement that the only thing at this point is the flange.

Hopefully I'll have the car back today so I'll let you know how it goes. The flange is around £120, bearing is around £30, and with 2-3 hours work (I'm guessing) it'll probably be between £200 and £300. I'm happy to pay that as I've thrown too much money at this brake now!

Car has been repaired, £248 so very reasonable. Wobble and squeaking has gone.

But a new sound has appeared...

I get that sound sometimes when I pull away after using the brakes, and even sometimes driving in a straight line. It stops the moment I touch the brakes.

It's only happened since they changed the bearing/flange on that corner, and stops when braking, which pin points it to the N/S/F brake that's causing the noise.

The garage has told me there was a lot of movement of the pads inside the caliper when braking, and the pads are Eicher which I've now found by reviews to be awful. I'm wondering that, not that it's braking evenly, the pads are closer to the disc and are vibrating and causing the noise, where a more premium pad wouldn't?

Any thoughts are welcome.

Another video of the sound:

Update: IT'S FINALLY FIXED.

As you can tell from the video above, it was happening when driving without touching the brakes. After some research, here's what I think was happening...

Now that there is a new flange/bearing on the car, the disc no longer wobbles and is perfectly true. Because of this, the pads are able to sit closer to the disc (the wobble would have pushed them out slightly). The Eicher pads that I have in there are known to be horrendous quality, and they even look slightly different, which could cause them to rattle and vibrate if not seated properly. The garage even told me there was a lot of movement of the pad the carrier. Because they're now sitting closer/touching the disc as they should, they're vibrating more and causing that sort of harmonic resonance sound you can hear in the video. I realised that I still had the Brembo pads that I took off the car when I first changed it's brakes; they still had a lot of meat left on them and looked relatively new. I cleaned them up, swapped the Eicher's to the Brembo's and the sound is gone. I drove it for a good 40 minutes around town and there's no noise of vibration at all.

So there we go; a warped flange caused the brakes to wobble and squeak, and poor quality pads caused a groan/vibration when they were functioning as they should. I'm really hopeful that it's all done and I can forget about it. It's been 5 months of issues with this one brake since the day I've bought it, so now I can concentrate on other areas of it.

Thanks for the help everyone!