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Just an "FYI" I suppose, as a data point - I picked up a CPO'ed 15 Macan S, and at 38K miles - front right wheel bearing replaced (under warranty, no worries there). Diagnosed by a speed dependent sound starting clearly around 30/35mph, loud around 45mph, very loud at 60mph+ , steering input to the left increased the volume of it, steering input right decreased it.
 

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Since it's an FYI, would you care to share the type of sound this worn wheel bearing made?

When you were driving with the failed wheel bearing, could you tell where the sound originated?


Thx!
 

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Since it's an FYI, would you care to share the type of sound this worn wheel bearing made?

When you were driving with the failed wheel bearing, could you tell where the sound originated?


Thx!

Had one go bad at 44k in my S4 last Spring, and it sounded like a rhythmic roar that got louder as speed increased. Diagnosing is usually by turning at speed, and if it increases while turning right, it is most likely left wheel bearing and vice versa.
 
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If you've ever had a bad wheel bearing you will forever know the sound. I've ridden in many people's cars and been the one to break the news to them. They don't believe me at first but a few months later they report back.
Had both rears go out on a Subaru with 40k miles on it. The fronts on my boxster went out at around 120k. Nothing about this implies Porsche produced a bad car, though 40k is definitely on the low end.

FYI a TERRIBLE sounding bearing, when removed, feels "pretty good" when you spin them. ANY roughness in a bearing means it is junk.
 

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I have an early 2017 GTS (2016) and had both front wheel bearings replaced under warranty at 21k miles. I have experienced wheel bearing noise many times on other cars, so I noticed it on the Macan while it was still very subtle.
 

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Since it's an FYI, would you care to share the type of sound this worn wheel bearing made?

When you were driving with the failed wheel bearing, could you tell where the sound originated?
I just lost my second one in a '15 Macan that I CPO'd 4 years ago. It sounds like you're riding on the highway with mud tires. Kind of like how a pickup or jeep will mount aggressive tires and drive on the roads. It's hard to pinpoint though. It's just a general sound from the front. I assume it would sound like a general sound from the rear if a rear one had gone bad. When I lost the first one the dealer recommended I get new tires as they were getting worn. This was after driving it and saying "I'm not really sure, I don't hear anything". This time around I swapped my two front tires and the sound persisted from "sort of the driver side", so I knew it was the wheel bearing again. The dealer representative already had seen a bunch of these fail by now, so he knew by then what to look for.
 

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Thanks!

Chalk up another one for the Macan line! Wheel bearings failing prematurely. What happened to things
like this lasting 100K+ miles?

Sheesh...


:rolleyes:
 

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This is sort of surprising to me, for both Porsche and other makes. Loud bearings and roughness are associated with pitting failure, which is a fatigue mode called contact fatigue (as opposed to say, bending fatigue or torsional fatigue). Quite simply it’s a result of repeated cycles of pressure on the bearing race as it spins. The race will break in with a polished appearance and may later develop a matte frosted appearance. Eventually tiny pieces chunk away, leaving the race pitted and noisy. Run it long enough and it can even break into pieces (if you’re deaf).

Grit and repeated frequent impact can affect contact fatigue life. I’m not sure about preload or lubrication since they shouldn’t vary much. Otherwise it’s just the result of millions of revolutions, loading and unloading the race. The relationships between cyclic stress and life are a very well known part of a discipline called fracture mechanics. So it comes down to your car’s load history, bearing heat treatment, subsequent grinding (which if not we’ll controlled can “burn” or damage the case, reducing fatigue life), and most of all, design standards.

Porsche could size bearings to tolerate all these variables and still provide nearly infinite fatigue life. Pick your target: 100,000 miles? 200,000? It appears they’re aiming low but it does keep weight and initial cost down. To upsize the bearing to reduce contact stress, everything in the system gets bigger, heavier, and more expensive. Sounds like other auto makers have similar standards. Aircraft bearings are designed FAR more conservatively!
 

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This is sort of surprising to me, for both Porsche and other makes. Loud bearings and roughness are associated with pitting failure, which is a fatigue mode called contact fatigue (as opposed to say, bebeing fatigue or torsional fatigue). Quite simply it’s a result of repeated cycles of pressure on the bearing race as it spins. The race will break in with a polished appearance and may later develop a matte frosted appearance. Eventually tiny pieces chunk away, leaving the race pitted and noisy. Run it long enough and it can even break into pieces (if you’re deaf).

Grit and repeated frequent impact can affect contact fatigue life. I’m not sure about preload or lubrication since they shouldn’t vary much. Otherwise it’s just the result of millions of revolutions, loading and unloading the race. The relationships between cyclic stress and life are a very well known part of a discipline called fracture mechanics. So it comes down to your car’s load history, bearing heat treatment, subsequent grinding (which if not we’ll controlled can “burn” or damage the case, reducing fatigue life), and most of all, design standards.

Porsche could size bearings to tolerate all these variables and still provide nearly infinite fatigue life. Pick your target: 100,000 miles? 200,000? It appears they’re aiming low but it does keep weight and initial cost down. To upsize the bearing to reduce contact stress, everything in the system gets bigger, heavier, and more expensive. Sounds like other auto makers have similar standards. Aircraft bearings are designed FAR more conservatively!
So what I did on my Ducati was take all these notes of yours into previous consideration and make a strike ahead of failure. I changed them all before they failed. Wheel bearings are universal in sizing so it matters not where you are you can find replacements, not as convenient as your own garage, of course.
 

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I just had the front passenger-side wheel bearing replaced in my 2015 Macan S at a local (NH) Porsche dealership. I had just turned 81k on the ODO. The cost was $1308, including a 4-wheel alignment. The breakdown of the invoice is as follows:

Install angular ball bearing $253
Install countersunk head screws (4) $25
Install hex nuts $9
Install hex-head screw $22
Install pan head screw 14 x 11 (2) $18
Labor $716
Perform 4 wheel alignment $230
Shop supplies $35
 

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Thanks!

Chalk up another one for the Macan line! Wheel bearings failing prematurely. What happened to things
like this lasting 100K+ miles?

Sheesh...


:rolleyes:
Do you really think there’s much of an issue here? Granted wheel bearings should not fail this early, but the number of failures reported is so minimal it does not seem to be much of an issue.

Sure, it’s an issue for whichever owner has the problem, but overall the likelihood of any one owner experiencing a failure prior to 100k miles seems pretty remote. I actually had a wheel bearing crack on a Mini with only a few thousand miles on it, but I don’t recall hearing even one other owner that suffered the same problem.

Reminds me of the forum member who recently had a PDK failure at 90,000 miles. Of course it should not happen, but few vehicle manufacturers can claim zero transmission failures at less than 100,000 miles.

I also wonder if Porsche owners are more likely to speak up about an issue like this. If this was a Hyundai foum and an owner had a wheel bearing failure, would they even bother to post about it?
 

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I also wonder if Porsche owners are more likely to speak up about an issue like this. If this was a Hyundai foum and an owner had a wheel bearing failure, would they even bother to post about it?
Probably not, in large part due to the cost of repair being substantially less!
 

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Probably not, in large part due to the cost of repair being substantially less!
If the truth be known, I would not be surprised if the wheel bearings used in the Macan are interchangeable with some other cars and sourced from the same supplier.
 

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If the truth be known, I would not be surprised if the wheel bearings used in the Macan are interchangeable with some other cars and sourced from the same supplier.
The wheel bearings used on the first generation Macan are the same exact wheel bearings Audi used on most of its models from roughly 2009 until 2017 or so. Feel free to pay more if you want the box to say Porsche on it instead of Audi. Better yet, aftermarket bearings from Timken, Moog and Centric are widely available in the $100 to $130 range. In fact, I’m under the impression VAG sourced most of these bearings from Timken.
 

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I suspect bad wheel bearings in my '15 S. A very slight but constant woo-woo sound has started, most noticeable at speeds over 30mph, not drivetrain related as it happens when coasting too. Definitely not the exhaust mid-pipe issue either as i had new flex joints welded in by an indy a while back. Not A/C either.

Any other ideas on what it could be?

Alternatively, anyone know if a front wheel bearing swap is an easy DIY? Or do all the suspension components need to be loosened (like in my GTi)?

Any guidance is appreciated.
 

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I suspect bad wheel bearings in my '15 S. A very slight but constant woo-woo sound has started, most noticeable at speeds over 30mph, not drivetrain related as it happens when coasting too. Definitely not the exhaust mid-pipe issue either as i had new flex joints welded in by an indy a while back. Not A/C either.

Any other ideas on what it could be?

Alternatively, anyone know if a front wheel bearing swap is an easy DIY? Or do all the suspension components need to be loosened (like in my GTi)?

Any guidance is appreciated.
Any resolution to this?
 

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Probably not, in large part due to the cost of repair being substantially less!
Not sure why someone would claim this. Actually if you price out wheel bearings for a Macan versus a Santa Fe you’ll see the equivalent bearings for the Macan cost less! The labor at a garage will be the same as it is essentially the same exact job.
 

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Any resolution to this?
Just back from a 3000 mile trip and I can conclude that it isn't the wheel bearing as the sound has not changed. It did become a knocking sound on a really rough section of road for a short while which makes me suspect that the exhaust pipe is the culprit.

I think the whole pipe is oscillating or moving and this constant movement creates this annoying sound. All the brackets are fine but the rear part of the system does have a fair bit of movement anyway.

I'm going to swing by a good exhaust shop in the new year to see what they think.
 
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