New caliper or rebuild?

[spartacus68]

Polo 1.4TDI on 15 plate. I've been working from home for the last 5 months, so haven't driven it much. My wife's BMW was in the garage so she borrowed the Polo for the last 2 weeks. Looking at in the street, the front wheel is contaminated with brake dust.

Out today and there's a reverberating sound, possibly N/S front. Couple of other things. I fitted new Brembo discs and pads all round 2-3 weeks ago. Didn't notice an issue with the caliper pushing the piston back in when I was working on it. Used Pro slip on the pads, brake sliders, etc.

When I was out I did a coast to stop, so there is heat on the N/S front. Not excessive though. Car only on 40k miles.

I've used Bigg Red brake rebuild kits before so happy to use this approach. The piston dust sleeve was intact, I remember that.

Couple of questions. Eurocar parts have Pagid caliper for £109. Long term I know this is the right approach, however, could a bad bearing cause this issue forcing the pad to contact the rotor? Don't want to swap out a perfectly good caliper if it turns out it's the bearing.

[RUM4MO]

It seems a bit annoying to have front brake issues at that age/mileage, which size of brakes are on the front of that car, if they are 256mm are they ATE FS111 or are they something else, like Mando?

I'd think, unfortunately, if they are Mando then could be the source of your problems, and getting a pair of refurbed ATE FS111 callipers might make your troubles disappear for ever.

VW Group started using Mando instead of ATE probably to save lots of money, and some people have been finding that maybe the sizing is not as accurate as you might like, so did you check that the new pads were free enough to move along the calliper carrier before reassembling the front brakes.

It is easy standing back from this and thinking about giving a new "dog" (Mando) a bad name, but it might deserve it.

I'm lucky, my wife's 2015 Polo 1.2TSI 110PS has 288mm front discs so got ATE C45 - I think callipers.

[spartacus68]

Thanks RUM4MO. Bery interesting. They are indeed 256mm discs. Didn't have to force the pads on, they went on fine and used Pro Slip grease. Would you completely avoid a brake rebuild?

The external part of the caliper looks clean, and the dust cover was intact, and I don't remember any friction pressing the piston back in.

I was going to pop out the piston, use new Bigg Red dust sleeve and brake 'o' ring seal and lightly grease with red grease. Are Pagid calipers any use?

[Cal844]

Buy a remanufactured (rebuilt) caliper ready to fit, I personally do this so that I don't risk the safety of people in my car. I've only had one faulty remanufactured caliper but it was for a 2010 Fabia and was discovered to be faulty during fitting.

You'll also get a surcharge on your old unit.

Have you made sure the flexi hoses are not breaking up internally, I've had this after 4 or 5 years on my classic minis.

Hope this is some help in your decision.

Cal

[RUM4MO]

I think that generally speaking, Pagid refurbished callipers will just be either new(if you are lucky) or older but fully refurbished ATE callipers or callipers from another aftermarket provider.

My only unknown is "will a slightly earlier ATE FS111 calliper fit that calliper carrier?" maybe checking part numbers for both versions of callipers would answer that, VW Group use "MAN" to signify Mando as the manufacturer.

So, has that calliper for a 256mm front brake got FS111 cast into its outer facing body?

[spartacus68]

Update to this. Finally had a bit of time at the weekend and stripped down the caliper. Before I got to that bit I found a stone that was wedged between the brake pad and hub. Up in Scotland, they do like to top dress roads rather than resurface, certainly on A-class and back roads. I thought fantastic, there's the cause. Anyway, stripped the caliper down and popped out the piston. Piston bore was clean, I mean no corrosion. Also dust sleeve intact too. Used some red grease under the sleeve, and the piston retracted easily. Did a brake bleed all round.

I'm thinking I've sorted things, but prepared to replace the caliper if need be. Bigg Red do exchange ATE units, so that's my next option.

Popped over to my brother on dual carriageway, and here's the key thing. Prior to getting there, car was quiet, no noise. As soon as I came off A-Road and on to dual carriageway, after about 30 mins, I can hear a drone. Anything above 50mph, and there's a little heat on that corner.

Anyway, FAG bearing and hub ordered. Looked at a few videos, and quite honestly dropping lower balljoint, pressing out bearing, I thought, for £70 including a new hub, just change it.

Suspect pothole or similar could be the cause. Car drives straight, but at 40k miles I am surprised.

[spartacus68]

So I'm going to need a bearing tool to change. I see Laser make one for all VAG models, but at over a £1k, that's not an option. Are the Ebay ones an use and can anyone confirm is it 72mm please?

[RUM4MO]

My take on this "bearing changing" topic is, for me Gen2 bearing/hub assemblies do need special tooling to get that job done right first time, the snap ring which retains the assembly into the hub carrier is very easily damaged and/or the assembly is not pressed in far enough to fully engage that snap ring - so with time the bearing assembly wanders back out, hopefully causing ABS warnings before doing too much damage to the hub carrier - and by then maybe the snap ring is U/S meaning you need to find more cash to buy another hub/bearing assembly.
So for this job, you either buy a proper expensive kit of bits - or get a proper workshop to change that - maybe even a smart workshop that can do that work while the hub carrier is still mounted on the car.
I'm sure that I have read, as maybe you have, sad tales of people getting an ordinary workshop not clued up or tooled up for these modern bearings, doing the job quickly and cheaply - then needing to revisit that repair a few months down the line, either due to ABS warnings or/and issues with the pads wearing unevenly as the floating calliper can not move far enough to straddle the disc which has moved out a bit.
It seems that the industry intends to move onto Gen3 hub designs which means that a larger assembly is now a "bolt off - bolt on" job, which costs more in material but a lot less in labour, and probably returns this job to being easily a DIYer activity.

[spartacus68]

Thanks RUM4M0.

Oh the joys of Gen2 bearing assemblies. VW obviously didn't think that one through. The Gen3 is a simple unbolt and bolt procedure on the A4 for example.

I've looked at a few videos on this Gen2 procedure, and it doesn't look overly complicated, and there's an 'audible click' once the snap-ring engages. From what I can see from online tutorials - you continue to press home the bearing until fully seated in the hub carrier.

Regards the ABS sensor - it can be removed prior to the procedure which I'd be inclined to do. Laser make a tool that can fit the bearing with the sensor in situ. Anyway - I'm undecided. Have had a big bill on my wife's i3 that the so-called tech experts at BMW failed to diagnose, even although I pointed them to the fuel pump relay from the outset. Anyway - that's for a different forum!

FAG Tutorial: https://www.youtube.com/watch?v=rUZ_B-qgb0k

Excellent driveway tutorial: https://www.youtube.com/watch?v=wmJPW39ufV4

[amer6R]

You can even change it without "special tool", but its fiddly

[RUM4MO]

I'd think that the reason that these cars have GEN2 front wheel bearings is that this area of these cars dates back to at least 1998, so predates any designs beyond basic GEN2.

Like you have found, I'd think that these jobs have, with the correct tools, been de-skilled, so a monkey could change them and end up with a perfect job.

[spartacus68]

Prep work for bearing change next weekend. Dust shield comes off and ABS sensor pulled. This is the kind of stuff that turns a job into a nightmare. Bearing definitely goosed. Hard to turn and rough.

20200829_124458.jpg

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[RUM4MO]

We want to be able to see these pictures!!

[spartacus68]

We want to be able to see these pictures!!

Something strange with this site.

[spartacus68]

Fitted the bearing today between showers. Nothing unusual. Knowing the ABS and brake dust shield would come off as I did the preparation last week was a bonus. This is an excellent video if you're attempting it. I ordered a bearing puller tool from Germany. I had to remove the drop link to get the drive shaft out. Other than that, go slow and it's straight forward.
https://www.youtube.com/watch?v=ZD--itvZ7cM&t=3s