[Chugga]

Hi all,

I have brake shudder when touching the brakes along with a bit of wheel wobble so assume front brakes. But, I also get some shudder when on cruise and have been advised its the rear brakes that manage the radar speed, is this correct?

Its not excessive, more annoying, and is getting worse and will soon be towing a 2000KG camper trailer so want to get sorted.

The brakes have been looked at and plenty of meat on them, were changed 20k ago.

Before I get new disks, can I get a light skim to see if it rectifies? I know with the euro disks it's sometimes not recommended.

Any other info much appreciated!

Thanks

 

[jeffnhiscars]

It would help to know the year and model but the tolerances on these rotors are tight so skimming is not an option AFAIK.

 

[Chugga]

It would help to know the year and model but the tolerances on these rotors are tight so skimming is not an option AFAIK.

Thanks for the feedback, 2015 V8

 

[rgh0]

Tolerances specified on disk wear by VW are tight and tighter than they potentially need to be. Skimming is possible within the VW tolerances and more depending on your personal judgement. Bearing wear and pad condition and disk glazing and uneven wear can all cause problems. A starting point is take the car out and do 5 or so hard stops from 100 kmh down to 30 kmh over a short time and see if it improves.

cheers
Rohan

 

[TommiT]

There is only 1mm of wear on each side of discs so a skim on worn discs may not be possible without taking the discs under the recommended service thickness.

If the discs and pads (presumably both were changed at the same time) are only 20K old then personally I'd take the wheels off and measure the discs' run out before replacing anything and, although you say it's been done, carefully inspect the brake components.

And while the wheels are off I'd get them rebalanced.

 

[brickwalls]

Thanks for the feedback, 2015 V8

At only 20km on the rotors I'd be looking at tyres 1st. Also look for hot spots on the rotors. I'm most conservative during 1st 500km when running in new rotors, pulling up well back from car in front at traffic lights and creeping up so if the pads are overheated they don't sit in the one spot.

 

[paulie0735]

If I'm reading your post correctly the pads were changed 20k ago but the rotors are the originals? If that's the case then I suspect your rotors are shot. The brakes fitted to these cars are designed and intended to be changed as a full set, Pads, Rotors and Sensors. Its not cheap but its a cost that needs to be considered when buying these cars. That doesn't mean you have to pay the ridicules money that VW Dealers want to do the job but there is no cheap option either.

 

[Chugga]

If I'm reading your post correctly the pads were changed 20k ago but the rotors are the originals? If that's the case then I suspect your rotors are shot. The brakes fitted to these cars are designed and intended to be changed as a full set, Pads, Rotors and Sensors. Its not cheap but its a cost that needs to be considered when buying these cars. That doesn't mean you have to pay the ridicules money that VW Dealers want to do the job but there is no cheap option either.

Hi, pads and rotors changed together by VW. Before I purchased the car though. First 2-3k, felt ok, then a slight shudder started. The car was a city car, assumed the previous owner may have been hard on the brakes, maybe I am too and have further created issues.

 

[Chugga]

At only 20km on the rotors I'd be looking at tyres 1st. Also look for hot spots on the rotors. I'm most conservative during 1st 500km when running in new rotors, pulling up well back from car in front at traffic lights and creeping up so if the pads are overheated they don't sit in the one spot.

Tyres were not so good when I purchased, as the shudder got worse, I assumed tyres. These were replace about 3k ago and shudder still there.

 

[Chugga]

There is only 1mm of wear on each side of discs so a skim on worn discs may not be possible without taking the discs under the recommended service thickness.

If the discs and pads (presumably both were changed at the same time) are only 20K old then personally I'd take the wheels off and measure the discs' run out before replacing anything and, although you say it's been done, carefully inspect the brake components.

And while the wheels are off I'd get them rebalanced.

I’ll do the run out, this will be a good test. When feeling the rotors, they seem almost a convex shape, like the rotors have worn at the top and bottom and not across the entire rotor.

 

[TommiT]

If you have uneven wear could this be down to an iffy caliper piston?

If you measure the run out it might be worth using calipers to measure the discs' thickness in several places across the diameter using the same places on each of the 4 discs to get a good comparison.

 

[brickwalls]

If you have uneven wear could this be down to an iffy caliper piston?

If you measure the run out it might be worth using calipers to measure the discs' thickness in several places across the diameter using the same places on each of the 4 discs to get a good comparison.

True that usually happens if the car sat idle for an extended period with moisture under the seal on the previous set of pads. The pistons are OK until they reached the dodgy bit in their travel again.

Crossing fords after extreme downhill runs can cause cracking. One of the few times I use the paddle shifters is to engine brake. Any Range Pass will show up vehicles with Automatic transmission as most folk just drive downhill on the brakes. But it takes over 1000C to soften standard rotors and you'd smell overheating pads first, a visual check will show discoloration patches on the rotors.

Sloppy suspension bits can also feel like brake shudder but won't be as rhythmical at low speeds.

There is a lot of debate on skimming VW rotors as they're part of the sacrificial equation and skimming can change the surface structure. There are better options for less money out there than the genuine ones JIMHO, and most of them can be machined.

If the rotors were changed by previous owner check the brand & logbook. There were a lot of nasty rotors with Gentrified English sounding brand names going around a couple of years back at less than $300 a set - delivered.

 

[DugSms]

Hi all,

I have brake shudder when touching the brakes along with a bit of wheel wobble so assume front brakes. But, I also get some shudder when on cruise and have been advised its the rear brakes that manage the radar speed, is this correct?

Its not excessive, more annoying, and is getting worse and will soon be towing a 2000KG camper trailer so want to get sorted.

The brakes have been looked at and plenty of meat on them, were changed 20k ago.

Before I get new disks, can I get a light skim to see if it rectifies? I know with the euro disks it's sometimes not recommended.

Any other info much appreciated!

Thanks

This part: "But, I also get some shudder when on cruise and have been advised its the rear brakes that manage the radar speed, is this correct? " seems a bit suspect to me.
If you have issues while driving and not applying the brakes, I would not assume it is either the front or rear brakes. I would be focused on either wheel bearings or suspension components. End link stabilizers, tie rod ends, and ball joints are usually the first things I check as those tend to be cheaper and easier to replace. Next items would be shocks/struts and mounts for them.
Do you notice any noise when going over bumps? Thumping or creaking noises, for example.
Have you had the alignment checked?

 

[mycoman]

I have a 2016 with a similar condition. When I purchased it with 30k miles I didn't notice this during test drive. But I did notice a slight shudder occasionally when breaking, but not consistently. I replaced pads once and the rotors looked fine. Now at 80k miles, I feel a slight shudder occasionally when coasting at around 35 mph. I am still at a loss for what can cause this, but suspect that it might be related to some automatic braking function.

 

[Snerlo]

I've heard alot about making sure the wheel nuts are torqued up properly and in the correct order so have you tried this approach before replacing parts. Just a suggestion to try first.

 

[Chugga]

This part: "But, I also get some shudder when on cruise and have been advised its the rear brakes that manage the radar speed, is this correct? " seems a bit suspect to me.
If you have issues while driving and not applying the brakes, I would not assume it is either the front or rear brakes. I would be focused on either wheel bearings or suspension components. End link stabilizers, tie rod ends, and ball joints are usually the first things I check as those tend to be cheaper and easier to replace. Next items would be shocks/struts and mounts for them.
Do you notice any noise when going over bumps? Thumping or creaking noises, for example.
Have you had the alignment checked?

Hi, thanks for the feedback,
Driving is ok, it’s only when I apply the brakes, alignment was completed when new tyres installed. The rear end, especially rear left seems a bit clunky going over speed bumps. It’s being serviced this week, I’ll get them to have a good look.

 

[Chugga]

I've heard alot about making sure the wheel nuts are torqued up properly and in the correct order so have you tried this approach before replacing parts. Just a suggestion to try first.

I also heard the same, and have reset the torque on the bolts, unfortunately made no difference