All 4 of my brake disc shields have badly corroded. I have replaced the front ones which was quite straightforward. I have now started on the rears but discovered that to do them properly you have to remove the hub.

 

The front shields are shaped like the letter 'C' and can be slid behind the hub without removing it. The rear shields have a large hole in the middle rather than being 'C' shaped but the hole is not large enough to fit over the hub. See the attached pictures.

 

My question is: I don't really want to remove the hub so is there any good reason why I shouldn't cut the shields so that they are more like the front ones and then I can just slide them behind the hub?

 

The position where I would cut it only has a very thin strip of metal so it would not compromise the strength greatly and I would paint the cut ends.

 

Thanks,

 

Kevin

I did exactly that in the summer when I changed all discs because I didn't realise the rear hub had to come off, I just cut a section out with an angle grinder and splashed a little anti corrosion paint on them and hey presto as good as new!

Mine came loose on the back. I decided to cut it off.

 

I knackered the sensor ring on the hub while doing it and ended up getting the hub done anyway. It was rusty and probably pretty delicate anyway.

 

Something to bear in mind while you operate.

Thanks for the info guys. I'm going to cut the new shields and avoid interfering with the hub. I'll try to take some pictures and post them after I've done the job.

I did the job today; it probably took me about 1 hour per side. Here is the procedure on a 2005 Octavia 2.0 TDi.

 

1. Remove the road wheel.
2. Remove the brake calliper (15mm & 13mm spanners).
3. Disconnect the ABS sensor connector and loom. You need to be careful not to snap-off the release clip. Sometimes pushing the connector on more can help when trying to lift the clip. If you are not familiar with the plugs then look online for a guide otherwise there is a high probability that you will break it!
4. Remove the brake calliper carrier mounting bolts (M14 splined tool). These bolts are very tight so make sure that the tool is FULLY inserted before applying any force. If you are doing the job on axle stands then you will need to be cunning with how you loosen them. I had a long M14 spline bit (see photo) which allowed me to attach a ratchet at one end on a long extension and fit a large adjustable spanner across the flats of the bit. I pre-load the ratchet using a trolley jack under the handle to apply the force. I then used a small lump hammer to hit the handle of the adjustable until the bolt finally 'gave'.
5. 
6. The carrier and pads can be left on the disc.
7. Unscrew the T30 disc retaining bolt.
8. Remove the disc from the hub. If the disc is seized to the hub then heat the disc in the area of the road wheel bolt holes using a blow torch. A tap with a lump hammer behind the disc should then release it.
9. If necessary hacksaw through the old disc shield at one end of its narrowest section and bend the narrow section out of the way.
10. 
11. Remove the corroded disc shield using a T30 bit. Make sure that they are fully inserted before applying any force.
12. Cut a 55mm section out of the new shield (see photo), de-burr and paint the cut edges.
13. 
14. Slide the new shield in place and reassemble.
15. 

 

This procedure avoids having to undo the hub bolt which requires an M18 splined bit which needs to be replaced when refitting. I am unsure as to the purpose of the disc shields but the manufacturer would not have bothered to add weight and cost to the car had their engineers not believed there was good reason.

 

 

1st post

 

Thanks for this thread, it's just made a massive difference to helping me sort a loose shield at pretty short notice on a 'new car'. The corrosion on mine as purely around the head of the 3 bolts retaining the shield so I've just put a large head washer underneath each screw head and done it back up with a dab of thread lock.

 

The caliper retaining bolts were indeed a swine and just before I gave up I found that by using the attachment in my socket set that lets you put a bar through the back of the socket BUT using a Draper extending wheel wrench which has a 70ish degree bend in it, this gave me articulation that the handle came outside the wheel arch and with 500mm of leverage both bolts came undone ( http://www.mad4tools.com/extending-vehicle-wheel-nut-wrench-9773-p.asp?gclid=CJzer5HDh8YCFdQZtAodFXIA2g ).

 

The only thing I found is you need an M14 spline bit with a relatively short spline on it else if fouls on the hub / wishbone or somthing (can't remember now). The one I bought originally had a 80mm length which was too long.

I replaced my rear shields last year & cut them as i didnt want to remove the rear hub,i didnt touch the abs sensor or wiring though when i replaced mine. 

I'll be doing exactly this some time soon, just had to cut a loose one off yesterday to stop the horrendous rattle.

I chucked them into bin. Most useless part of car, which overheats brakes and don't help anything - where you need dust cover is open area and where should be disc vented is covered by thermal shield aka "dust cover"