Rusted Brake Shield

163,300 miles, 24th April 2015

Occasionally, over a couple of years I used to hear this weird metallic clunking noise coming from underneath the car, usually when turning at slow speeds (less than 20mph). It sounded a bit like I imagine an exhaust would sound if it were loose. I looked underneath the car a couple of times half expecting to see something hanging loose but everything looked fine. As the car was running fine, and I sometimes went months without hearing the noise, I assumed it couldn't be anything serious. Fortunately I was right.

Rusted brake shield with loose bottom section.
Click on photo to enlarge.

Rusted brake shield from rear.
Click on photo to enlarge.

I found the cause one day by accident after I had removed the rear driver's side wheel. I noticed that the brake shield fitted behind the disk was rusted through. When I looked more closely I found a sizable section hanging loose. A bit of wind could easily push it either into the side of the brake disk or the inside of the wheel. Indeed, the inside of the wheel showed scour marks that appeared to confirm my theory.

Inside of wheel showing scour marks caused
by a loose section of brake shield.
Click on photo to enlarge.

After doing a little internet research it turned out to be a common problem, not just with Golf Mk 5's. Replacing a rusted shield didn't appear to be a particularly big or expensive job. Replacement shields are relatively inexpensive but fitting involves removing the brake calliper and disk. Many people just cut away any loose sections and continue driving with no other ill-effects. The only possible problems I suspect being possibly reduced braking performance in wet conditions when more road spray might reach the brake disk and greater chance of a stone or other foreign object getting into the brakes. I've had this happen to me twice already, even with intact brake shields!

Repaired rusted brake shield.
Click on photo to enlarge.

I checked the other shields on the car and whilst rusted, they weren't in too bad condition so I decided to go with the easy fix and just cut away the loose section of shield. I could actually pull the loose bit off with my fingers. Then I then used my little Dremel multi-tool to cut back to firm metal and make sure I didn't leave any sharp edges.

If another shield starts to disintegrate I think then I will then have a go replacing them.