Mk7 Golf GTI - severe scoring of rear discs

[Maxym]

A test with emory got rid of a lot of the 'scoring' and made the surface pretty smooth. At the weekend I'm going to give the whole rear discs a going over plus some hard stops and will see what results. More pics anon.

Thanks for all your input so far.

[nickfrog]

Good to hear. Tbh I am not really surprised - you won't need much emery scrapping as the rest will go in the space of a week with a bit of heat in them.
Changing discs and pads would have been totally unnecessary.

[james_gt3rs]

280E said:

Do you really clean your brake calipers? Is this 'problem' merely cosmetic?

Sometimes brake dust builds up between the pad and caliper and can give a funny pedal feel and noise. Taking pads out and spraying with brake cleaner has helped me in the past.

[TwistingMyMelon]

My Leon has similar on rear discs for last 2 years / 20 k miles, rear brakes are quite "loud" when you first use them

Local garage that does servicing always notes it on service sheet, but tells me he sees it all the time on VW group cars and nothing to worry about, he told me I dont brake hard enough so they dont get used enough to clean them off!!

My pet hate is drivers who ride/always use the brakes, I always try and carry speed through corners and avoid heavy braking, guess the rear discs don't get used much

Often journeys are just me in car, so a light load, or longer journey with kids, where I just drive carefully

Edited by TwistingMyMelon on Friday 3rd March 10:14

[Chr1sch]

My mk7 gti has done 20k, doesn't look anything like that!

[Sheepshanks]

TwistingMyMelon said:

My pet hate is drivers who ride/always use the brakes, I always try and carry speed through corners and avoid heavy braking, guess the rear discs don't get used much

As has been mentioned a couple of times in the thread, you'll find increasingly cars will apply the inside (of the corner) rear brake to help the car turn. Some cars, last 5 Series for example, are noted for eating rear brakes due to this.

[Maxym]

Update... Spoke to VW dealer today, who say that their observations on the rear discs were just a 'heads up' for my info. Well they did suggest they change the discs and pads and reminded me about it a couple of months ago. Money-grabbers. Turns out the situation isn't even half-way dire or even that abnormal. Pah! As I thought...

Interestingly the rear pads are 30% worn and the fronts only 20%. I suspect that could be down to the car having the Performance Pack with bigger front discs.

Over the weekend I cleaned up the discs with emory (made them a smoother though they didn't look that different) and drove 200 miles doing pretty heavy stops when I could. Made no difference to the appearance of the discs.

So everything's staying as it is. In future I will carry on braking in the intelligent fashion that has served me well for decades but do a short drive after washing the car so as to dry the brakes off (I do this with my Porsche anyway).

Thanks for your input, folks. Case closed.

[pixelmix]

Thread resurrection!

My 7 year old Mk7 GTI got some new rear discs and pads about 3.5 years ago but the new discs are now quite pitted already (slight vibration when braking hard from high speeds). The car is used for a mix of 70mph dual carriageways (with adaptive cruise) and spirited rural roads. I use the brakes pretty hard on local roads so I had hoped that I was clearing off the rust quickly enough, but there is a bit of a messy lip developing on the edges of the rears and they appear to have gone from fine to pitted pretty quickly. Two sets of discs in 7 years / 65,000 seems crazy (I only just changed the fronts for the first time, when the pad sensor triggered a couple of months back).

My slightly damp garage over winter probably doesn't help (I try to drive round the block now after cleaning the car to dry the brakes but the car doesn't really dry when driven straight in over winter). I'm wondering if there is any truth in the suggestion that Mk7 Golfs wear the rears when using the adaptive cruise?

Other than rebuilding the garage so the car isn't sitting in a damp over winter (on the long to do list!), are there any other tips or suggestions for rear discs that seem to not suffer from pitting quite so much?!

Edited by pixelmix on Tuesday 15th June 19:26

[Polome]

I had the rear discs on my polo gti showing signs of surface corrosion..for a couple of weeks I tried hard braking but found out the harder you brake the weight transfer goes more to the front ,the brake compensator can actually close reducing the pressure to the rear brakes actually increasing corrosion. The fact my car only ever had one person in it made matters worse. In the end I run with a very heavy bag of sand in the boot increasing rear axle load..this then needs more brake pressure and the discs cleaned up in a couple of weeks. As a bonus it made the car a bit more comfortable , ie the suspension working with the extra loading reduced the light car bounce. Good luck with fix.

[Smint]

New to the family 16 plate Golf, one rear disc exactly as in the OP's pic less than 20k miles, other disc perfect.
As almost always its lack of correct brake servicing, in the family car's case meant one pin seized.
Squirting brake cleaner liberally about through and from behind a still fitted wheel is not, never has been and never will be, correct brake servicing.