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There are quite a few threads about the brakes on the Gen 2. I thought I'd bring the two together into one thread so here it is.

One is that the brakes click at slow speeds - usually when going from forward to reverse or vice versa such as in a parking lot.

What you're hearing/feeling is the pads moving in the calipers.
These calipers are either based on or once were racing components. They were designed for quick pad change. There's one big pin that holds the pads in. In the racing world, you pull a retainer clip, yank the pins and the pads darned near fall out. Get around a a race car and you'll hear all sorts of loose things, clanks, bangs. They're not customer friendly.

Putting them on a road going car required making the pads more daily livable. This meant adding two (pain in the butt) springs to keep the pads pulled into position and a plate across them, held in by the big pin (designed to pinch our fingers when removing, darn it) to keep the pads from rattling around. The little amount of tolerance to allow the pads to be changed quickly (race) lets them move around in the caliper. It's not a big deal. It goes "click" when it happens. The pads probably move just a bit more than the thickness of a couple of sheets of paper.

So where am I going with this???

I just got off the phone with Audi North Scottsdale. I took my V10+ in for shuddering brakes and two TSB (technical service bulletins). One for clicking pads, one for an ECM update.

Fortunately Audi North Scottsdale is one of the dealerships that is part of Audi's technical issues gathering. They had one of the higher up (German?) Audi Techs here this week looking at, you guessed it, another V10+ with clicking and shuddering brakes. I just happened to pick a lucky day to take mine in.

The TSB on the clicking pads is directly in response to what I put in the description above.

Audi, in all their wisdom, decided that putting a little strip of double sided sticky tape on the back of the pad, where it touches one of the pucks, would stop the clicky, clicky. Nah. As soon as you get the brakes heated up, the sticky tape gives up and the sound is back. I believe two forum members have had this done and then said "It didn't work."
It's the nature of the brakes. Plain and simple. Get over it, live with it. I'm going to.
There is NOTHING wrong or being damaged. My Gen 1 did it also (same parts, I believe). It's funny, though, as I can't recall anyone on this forum ever speaking up about it with a Gen 1.

I was also informed that the TSB on this is going to be closed soon (was not told what soon was).

They've realized that the fix doesn't work so they'll sit back, scratch their heads and then offer up another TSB with some other way to fix it. (popsicle sticks shoved in the trailing edge side of the pad :cool:)

I was honest about the reason I took mine in too - I needed new front pads. Three track days and they're a bit thin. May as well take up the offer of replacing clicking pads with new ones, eh? My service guy laughed at me and said "No problem." - I asked them to bevel the leading edge of the pads about 1/4" (6mm) to help with the squeal that can occur and he said he's see what he could do. (Ironically, the Q5 has a severe squeak issue with the brakes and the fix was to bevel the edge of the pads.)

---------------

Second part: Shuddering brakes.

This one has them (Audi) scratching their heads. They are very aware of the issue and it seems to be the same across the board - very slow speeds, such as turning into a parking spot.

I threw this at them - total speculation on my part from a mechanical engineering perspective:
It's a combination of Ackerman, a front differential, suspension geometry and the suspension mounting components (rubber bushings).

When in the turn, you're loading the front suspension:
The car, with a diff up front puts some torsional loads across the front end - front wheels are pulling, it's a four wheel drive car
Ackerman has one tire pulling harder than the other, in other words it loads one side of the chassis differently from the other
Throw in a different rotational speed between the inner and outer wheel (outer wheel has a longer arc to follow so it turns more rapidly) and then apply a tad of clamping force (brakes) and you get a twisting, tugging load on the suspension.

The suspension mounts are all vulcanized rubber.
There's a steel tube in the middle that the mounting bolt goes through, the tube is surrounded by rubber and then that's all inside the end of the suspension component.

The rubber allows for the suspension to cycle (rotate around the tube, which is bolted into the suspension mount) but also provides a bit of damping of the chassis from road surfaces - in essence, all the rubber mounted suspension items are isolators.

Being that it's a rubber mount, there's the ability to deflect, albeit just minimally. So you put all those loads mentioned in the above through them and they complain with a shudder. It's suspension flex, if you will. As the brakes clamp, they cause a little spike through an already loaded system. It's just enough energy that when it's returned back by the rubber bushings, it overpowers the clamping of the brakes just ever so slightly and the wheel gets to spin just a tiny bit. The brakes overcome the sudden spike and get back to the business of stopping, putting that little shock load back into the system and it does it all over again and again - you get the shuddering cycle until you straighten the car (unload the suspension and bushings) or let off the brakes a tad. You'll notice that you can control how violent the shudder can by by how much you modulate brake pressure.

As stated, this is all just speculation on my part based on years of playing with vehicles, suspension design and a fascination with machines.

Guess we'll see what Audi comes up with. - have to admit it would be funny if they did come to a similar conclusion as this post. I'd have to ask them for a cookie and a gold star.
 

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Very informative post KfabR8 even though I don't personally own a gen 2. :)
 

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An update to a point: Audi is replacing the pads with a newer pad - it has radius'd edges. Squeak begone! - until you wear past the radius...
 

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What you stated above makes sense, but mine shudders in a straight line at very low speeds (less than 5mph) as well, why is that?
 

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What you stated above makes sense, but mine shudders in a straight line at very low speeds (less than 5mph) as well, why is that?
Because it doesn’t like you driving it slowly. :cool:

I have no clue. Have you done the TSB that puts new pads on it?
 

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Because it doesn’t like you driving it slowly. :cool:

I have no clue. Have you done the TSB that puts new pads on it?
Haha good one, I don't like driving her slowly either.

Do I need to receive a letter from Audi or do I just take it in and reference the TSB? Thinking I'll do it after track day.
 

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Haha good one, I don't like driving her slowly either.

Do I need to receive a letter from Audi or do I just take it in and reference the TSB? Thinking I'll do it after track day.
Definitely after tracking it - I needed new pads and blatantly took advantage of it.

I called my service tech first and told him that I was aware of the brake TSB and then he also informed me of the ECM TSB. May as well make a phone call and see what they say.

TSB for the brakes is TSB#2047140/3

The ECM is listed as "24CK Update for ECM Software" on my receipt.
 

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Definitely after tracking it - I needed new pads and blatantly took advantage of it.

I called my service tech first and told him that I was aware of the brake TSB and then he also informed me of the ECM TSB. May as well make a phone call and see what they say.

TSB for the brakes is TSB#2047140/3

The ECM is listed as "24CK Update for ECM Software" on my receipt.
j

Thanks, appreciate the info.
 

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Brough my plus is yesterday for the ECM and brake TSB. They changed the front pads and no more clicking noise when backing into my garage. It didn't bother me but I wanted the updated pads :)

Parts listed on my service receipt:
4S0698151M - Pads
4S0698269A - Hardware for pads
4S0615437B - Brake sensor

I haven't verified yet if the pads have a beveled leading edge but they haven't squeaked at all.
 

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I have a 2017 V-10 Plus which had the slow speed vibrating brake issue mentioned by several Gen. II owner's (including myself). After the third trip to the dealer they totally fixed it! It took getting the US service Rep. out here to San Diego and I was told they installed Lambo Huracan tie rod components, but whatever it was the problem is now totally solved.
 

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Can you provide some more details? Do you part numbers? This could be a big discovery if it truly fixes the problem.
 

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There are quite a few threads about the brakes on the Gen 2. I thought I'd bring the two together into one thread so here it is.

One is that the brakes click at slow speeds - usually when going from forward to reverse or vice versa such as in a parking lot.

What you're hearing/feeling is the pads moving in the calipers.
These calipers are either based on or once were racing components. They were designed for quick pad change. There's one big pin that holds the pads in. In the racing world, you pull a retainer clip, yank the pins and the pads darned near fall out. Get around a a race car and you'll hear all sorts of loose things, clanks, bangs. They're not customer friendly.

Putting them on a road going car required making the pads more daily livable. This meant adding two (pain in the butt) springs to keep the pads pulled into position and a plate across them, held in by the big pin (designed to pinch our fingers when removing, darn it) to keep the pads from rattling around. The little amount of tolerance to allow the pads to be changed quickly (race) lets them move around in the caliper. It's not a big deal. It goes "click" when it happens. The pads probably move just a bit more than the thickness of a couple of sheets of paper.

So where am I going with this???

I just got off the phone with Audi North Scottsdale. I took my V10+ in for shuddering brakes and two TSB (technical service bulletins). One for clicking pads, one for an ECM update.

Fortunately Audi North Scottsdale is one of the dealerships that is part of Audi's technical issues gathering. They had one of the higher up (German?) Audi Techs here this week looking at, you guessed it, another V10+ with clicking and shuddering brakes. I just happened to pick a lucky day to take mine in.

The TSB on the clicking pads is directly in response to what I put in the description above.

Audi, in all their wisdom, decided that putting a little strip of double sided sticky tape on the back of the pad, where it touches one of the pucks, would stop the clicky, clicky. Nah. As soon as you get the brakes heated up, the sticky tape gives up and the sound is back. I believe two forum members have had this done and then said "It didn't work."
It's the nature of the brakes. Plain and simple. Get over it, live with it. I'm going to.
There is NOTHING wrong or being damaged. My Gen 1 did it also (same parts, I believe). It's funny, though, as I can't recall anyone on this forum ever speaking up about it with a Gen 1.

I was also informed that the TSB on this is going to be closed soon (was not told what soon was).

They've realized that the fix doesn't work so they'll sit back, scratch their heads and then offer up another TSB with some other way to fix it. (popsicle sticks shoved in the trailing edge side of the pad :cool:)

I was honest about the reason I took mine in too - I needed new front pads. Three track days and they're a bit thin. May as well take up the offer of replacing clicking pads with new ones, eh? My service guy laughed at me and said "No problem." - I asked them to bevel the leading edge of the pads about 1/4" (6mm) to help with the squeal that can occur and he said he's see what he could do. (Ironically, the Q5 has a severe squeak issue with the brakes and the fix was to bevel the edge of the pads.)

---------------

Second part: Shuddering brakes.

This one has them (Audi) scratching their heads. They are very aware of the issue and it seems to be the same across the board - very slow speeds, such as turning into a parking spot.

I threw this at them - total speculation on my part from a mechanical engineering perspective:
It's a combination of Ackerman, a front differential, suspension geometry and the suspension mounting components (rubber bushings).

When in the turn, you're loading the front suspension:
The car, with a diff up front puts some torsional loads across the front end - front wheels are pulling, it's a four wheel drive car
Ackerman has one tire pulling harder than the other, in other words it loads one side of the chassis differently from the other
Throw in a different rotational speed between the inner and outer wheel (outer wheel has a longer arc to follow so it turns more rapidly) and then apply a tad of clamping force (brakes) and you get a twisting, tugging load on the suspension.

The suspension mounts are all vulcanized rubber.
There's a steel tube in the middle that the mounting bolt goes through, the tube is surrounded by rubber and then that's all inside the end of the suspension component.

The rubber allows for the suspension to cycle (rotate around the tube, which is bolted into the suspension mount) but also provides a bit of damping of the chassis from road surfaces - in essence, all the rubber mounted suspension items are isolators.

Being that it's a rubber mount, there's the ability to deflect, albeit just minimally. So you put all those loads mentioned in the above through them and they complain with a shudder. It's suspension flex, if you will. As the brakes clamp, they cause a little spike through an already loaded system. It's just enough energy that when it's returned back by the rubber bushings, it overpowers the clamping of the brakes just ever so slightly and the wheel gets to spin just a tiny bit. The brakes overcome the sudden spike and get back to the business of stopping, putting that little shock load back into the system and it does it all over again and again - you get the shuddering cycle until you straighten the car (unload the suspension and bushings) or let off the brakes a tad. You'll notice that you can control how violent the shudder can by by how much you modulate brake pressure.

As stated, this is all just speculation on my part based on years of playing with vehicles, suspension design and a fascination with machines.

Guess we'll see what Audi comes up with. - have to admit it would be funny if they did come to a similar conclusion as this post. I'd have to ask them for a cookie and a gold star.
Here is my take on your hypothesis...your theory related to suspension loading and rubber bushings in the mounts causing the noise would cause serious handling issues at high speeds when the dynamics you describe come in to play. If that were actually the cause you would experience abnormalities during high speeds while load shifting occurs. Therefore on those grounds I have to disagree with your hypothesis. This particular issue only occurs at very low speed and only "while braking". That noise is actually the pad releasing multiple times per second to prevent lock. I can duplicate the problem with scattered sand placed strategically in the entrance of a parking space.

So what is the fix?
The firmware could probably be improved upon using a new more advanced algorithm for the ABS system. In the meantime there is actually nothing wrong with the car and the noise/vibration is inherent and will not lead to any other issues what so ever.

Thank you so much for your post. When I visualized your hypothesis you brought me back many years to my old 75 GMC Jimmy which was full time 4X4. It had exactly what you described with respect to the geometry and the front diff dynamics and idiosyncrasies related to that design.
 

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The man that points to the suspension bushings is 100% correct as to the fix for shuddering brakes. When fixed, with all the right parts, the R8 braking system makes no clicks, no squeaks and no shudders. Totally quiet and as one would expect from a vehicle of that caliber.

The clicks and clanging over bumps is usually the pads moving in the calipers. Updated pads and retainers will fix that. Squeaking/squealing brakes are usually the compound and there is an updated pad for that too (assuming the vehicle hasn't been tracked or otherwise abused). Last the shuddering is a resonance/harmonic in the front suspension. Happens only under a specific set of circumstances, namely the level of friction between the pads and rotors, steering wheel angle, alignment angles, speed and some other variables related to the condition of the bushings. I've seen some cars do it going perfectly straight while braking at low speeds (these are the really bad ones) and others will do it only when turning slightly, usually more pronounced on one side and braking from low speeds, like in a parking lot. You can sometimes get the problem to go away by power washing the braking system. This temporarily changes the braking performance and makes them less "grippy". But in all cases, the only permanent fix was with a stiffer bushing in the control arms. The first guy who mentioned the Huracán arms knew what he was talking about.
 

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That clicking appear during ride or only when braking ?
I got similar noise to clicking- sometimes when I slowing down without braking, and also with.
Also squeaking with low speed ride straight.
 

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I have a 2017 V-10 Plus which had the slow speed vibrating brake issue mentioned by several Gen. II owner's (including myself). After the third trip to the dealer they totally fixed it! It took getting the US service Rep. out here to San Diego and I was told they installed Lambo Huracan tie rod components, but whatever it was the problem is now totally solved.
i have the same issue on my 17 V10+, shudder at low speeds, whole car shakes, any way you can connect me with the US service rep so I can get this fixed as well?
 

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I have a 2017 V-10 Plus which had the slow speed vibrating brake issue mentioned by several Gen. II owner's (including myself). After the third trip to the dealer they totally fixed it! It took getting the US service Rep. out here to San Diego and I was told they installed Lambo Huracan tie rod components, but whatever it was the problem is now totally solved.
i have the same issue on my 17 V10+, shudder at low speeds, whole car shakes, any way you can connect me with the US service rep so I can get this fixed as well?
 

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There are quite a few threads about the brakes on the Gen 2. I thought I'd bring the two together into one thread so here it is.

One is that the brakes click at slow speeds - usually when going from forward to reverse or vice versa such as in a parking lot.

What you're hearing/feeling is the pads moving in the calipers.
These calipers are either based on or once were racing components. They were designed for quick pad change. There's one big pin that holds the pads in. In the racing world, you pull a retainer clip, yank the pins and the pads darned near fall out. Get around a a race car and you'll hear all sorts of loose things, clanks, bangs. They're not customer friendly.

Putting them on a road going car required making the pads more daily livable. This meant adding two (pain in the butt) springs to keep the pads pulled into position and a plate across them, held in by the big pin (designed to pinch our fingers when removing, darn it) to keep the pads from rattling around. The little amount of tolerance to allow the pads to be changed quickly (race) lets them move around in the caliper. It's not a big deal. It goes "click" when it happens. The pads probably move just a bit more than the thickness of a couple of sheets of paper.

So where am I going with this???

I just got off the phone with Audi North Scottsdale. I took my V10+ in for shuddering brakes and two TSB (technical service bulletins). One for clicking pads, one for an ECM update.

Fortunately Audi North Scottsdale is one of the dealerships that is part of Audi's technical issues gathering. They had one of the higher up (German?) Audi Techs here this week looking at, you guessed it, another V10+ with clicking and shuddering brakes. I just happened to pick a lucky day to take mine in.

The TSB on the clicking pads is directly in response to what I put in the description above.

Audi, in all their wisdom, decided that putting a little strip of double sided sticky tape on the back of the pad, where it touches one of the pucks, would stop the clicky, clicky. Nah. As soon as you get the brakes heated up, the sticky tape gives up and the sound is back. I believe two forum members have had this done and then said "It didn't work."
It's the nature of the brakes. Plain and simple. Get over it, live with it. I'm going to.
There is NOTHING wrong or being damaged. My Gen 1 did it also (same parts, I believe). It's funny, though, as I can't recall anyone on this forum ever speaking up about it with a Gen 1.

I was also informed that the TSB on this is going to be closed soon (was not told what soon was).

They've realized that the fix doesn't work so they'll sit back, scratch their heads and then offer up another TSB with some other way to fix it. (popsicle sticks shoved in the trailing edge side of the pad :cool:)

I was honest about the reason I took mine in too - I needed new front pads. Three track days and they're a bit thin. May as well take up the offer of replacing clicking pads with new ones, eh? My service guy laughed at me and said "No problem." - I asked them to bevel the leading edge of the pads about 1/4" (6mm) to help with the squeal that can occur and he said he's see what he could do. (Ironically, the Q5 has a severe squeak issue with the brakes and the fix was to bevel the edge of the pads.)

---------------

Second part: Shuddering brakes.

This one has them (Audi) scratching their heads. They are very aware of the issue and it seems to be the same across the board - very slow speeds, such as turning into a parking spot.

I threw this at them - total speculation on my part from a mechanical engineering perspective:
It's a combination of Ackerman, a front differential, suspension geometry and the suspension mounting components (rubber bushings).

When in the turn, you're loading the front suspension:
The car, with a diff up front puts some torsional loads across the front end - front wheels are pulling, it's a four wheel drive car
Ackerman has one tire pulling harder than the other, in other words it loads one side of the chassis differently from the other
Throw in a different rotational speed between the inner and outer wheel (outer wheel has a longer arc to follow so it turns more rapidly) and then apply a tad of clamping force (brakes) and you get a twisting, tugging load on the suspension.

The suspension mounts are all vulcanized rubber.
There's a steel tube in the middle that the mounting bolt goes through, the tube is surrounded by rubber and then that's all inside the end of the suspension component.

The rubber allows for the suspension to cycle (rotate around the tube, which is bolted into the suspension mount) but also provides a bit of damping of the chassis from road surfaces - in essence, all the rubber mounted suspension items are isolators.

Being that it's a rubber mount, there's the ability to deflect, albeit just minimally. So you put all those loads mentioned in the above through them and they complain with a shudder. It's suspension flex, if you will. As the brakes clamp, they cause a little spike through an already loaded system. It's just enough energy that when it's returned back by the rubber bushings, it overpowers the clamping of the brakes just ever so slightly and the wheel gets to spin just a tiny bit. The brakes overcome the sudden spike and get back to the business of stopping, putting that little shock load back into the system and it does it all over again and again - you get the shuddering cycle until you straighten the car (unload the suspension and bushings) or let off the brakes a tad. You'll notice that you can control how violent the shudder can by by how much you modulate brake pressure.

As stated, this is all just speculation on my part based on years of playing with vehicles, suspension design and a fascination with machines.

Guess we'll see what Audi comes up with. - have to admit it would be funny if they did come to a similar conclusion as this post. I'd have to ask them for a cookie and a gold star.
did Audi scottsdale ever come up with the true fix or solution??? my 17 does the same thing, it's driving me crazy!!! I took it to Audi Chandler and they couldn't replicate it, never heard of this issue, gave the brakes a quick inspection and saw nothing wrong, I was left very frustrated! taking it to Audi gilbert next...
 

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You should drive around an video tape it if you can. That's the only way to push it if the dealer can't reproduce it.
 
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