100% drive unit failure rate??

[Max*]

If by "normal" you mean something wore or broke down and thus caused the noise? Then I guess it would be normal to hear the noise in that circumstance...

Whatever you choose to call it, it's not what's desired by Tesla or the owner. If it were "normal" or "desired" it would be there from the beginning and not develop over time.

Thank you and lol.

- - - Updated - - -

it would be there from the beginning and not develop over time.

Think of aged wine! Or stale cheese!

 

[davidc18]

Our 70D started out virtually silent. Now the whine from the front is loud enough to be heard on the interstate. It has been in to the SC twice. The first time they test drove it and told me they would order a replacement and swap it out at 5000 miles during the tire rotation. The test drove it again at 5200 miles (the whine was much louder) and decided it was "normal". We are now approaching 9000 miles and it is quite annoying and getting worse.

 

[AnOutsider]

Think of aged wine! Or stale cheese!

Ah, so "aging the DU" is like "breaking in the engine" in an ICE? :wink:

 

[mgdurand]

FWIW I put 40,000 miles on a noisy drive unit and had no problems other than the noise itself. It did get a bit louder during that time, but not by too many estimated decibels

The first one was replaced at 22K, then the second one started making noise by 30K. My third unit is a "P" so if it gets noisy I'll try to post something about it. The P now has about 15,000 miles on it i.e. a little more than the last one when it starting getting noisy, and so far so good, knock on wood. My car delivered in 3/14 and now has 80,000 miles on it.

Yeah, I listen to a lot of audiobooks.

So, I was not worried about the noise because I had done some research and the suggestion from old posts on this forum is that it is usually an electronic noise, not an actual metal bearing. I believe this, as the noise goes away when power is off, on regen or neutral i.e. not positive current flow.

Before I had the last DU replaced, I told the SC that I was going on a trip and was concerned about the noise. This was kind of BS since I am always going on a trip, but I wanted them to assure me of the mechanism behind the noise. Two long-timers independently told me the "milling" noise was an electronic noise, and just a "nuisance issue."

Neither one knew what electronic component was making the noise. I've read somewhere that there is an inverter mounted on the DU which has a rectifier which starts to hum - that was probably forum speculation, since that has to be a pretty easy fix, rectifiers are not... nah, that has to be BS. To me the noise sounds like a high frequency vacuum tube hum, though I'm guessing Tesla doesn't use too many vacuum tubes in Model S. No I'm not that old, grandpa left some radios behind. Anyway, whatever electronic component it is, is just vibrating and not apparently melting or otherwise becoming thermally damaged, at least not within 40,000 miles of use. BTW My driving habits are mostly cruise control on the Interstate, with the occasional push to remind me of the Ducati.

So from the customer side of things I'm pretty happy that Tesla will fix any nuisance issues for the next 6.5 years for free, so long as they are coming from the drive unit. From the stockholder perspective maybe not so much

Oh, one more thing, I was told that the SC's are moving toward having the DU's fixed in-house since it's just a "component," which can be swapped. Good.

 

[kort677]

I've stated this in numerous threads: Tesla's approach to the DU issue is to patch the problem; not engineer a solution.

I hope I'm wrong.

I am far from a qualified electrical engineer but I've been told that the DU problem is electrical in nature and it appears that there is some sort of flaw in the build/implementation of the unit.
since there hasn't been a fixed found for this reoccurring noise all that tesla can do is to replace the DUs on an as needed basis.
IMHO as long as tesla supports us by "cheerfully" making the swaps, which alleviates the problem, this is just a bump in the road, albeit a huge bump.
nonetheless it is a far from fatal flaw, and many of us have driven many, many miles with the problem.
hopefully a fix can be engineered and soon we can look back and just chalk up this problem to growing pains that are inevitable in maturation of a revolutionary technology.

 

[mgdurand]

It would be nice if Tesla were to issue an official statement on the matter, including the actual known mechanism for this noise. They have to have it pretty well pinned down by now!

If it's indeed an electronic component which doesn't fail in the functional sense, then it would be good for all of us to know, and good for the brand as well at this point. Because this DU noise is the main gripe, and with the Consumer Reports thing fresh, all the speculation amongst owners isn't helping.

 

[thegruf]

wasnt there a post recently about a delay in August getting a replacement DU, as there was a manufacturing hold for an upgrade.

Who know if this was the final fix, but it would seem they found something to be upgraded.

I guess Failures from manufacture date sept 2015 will be of interest.

 

[ohmman]

I think a failure implies a need of replacement. And I've mentioned this in "the other" drive unit thread, but we're all more than happy to have the DU replaced when they're covered by Tesla. However, once they're charging for it, I wonder how many people will consider it in need of replacement or just an annoyance.

Full disclosure, I had mine replaced at 20k and it was driving me nuts. I'd probably have paid some amount of money to replace it, but there's surely some number that would have made me classify it as an annoyance and not a failure.

 

[qwk]

While on the surface it may appear that way, none of us have any idea what's going on behind the scenes. They may in fact be doing engineering/design changes, and indeed that seems to be the Tesla way. That they aren't announcing those changes (other than Elon specifically and publically saying that there are multiple weekly changes being made to the car) doesn't mean they aren't happening.

Also of note is that many DUs have been changed proactively and some people seem to be lumping those in with the DUs that are being requested by owners.

To answer the OP's titled question: No. (And there's been plenty of proof of that on the forum for quite some time, as there is not proof in this thread.)

Excuses only work for so long. You forgot to take into account the dozens of revisions that are nothing but patches, and do not address the real issues. Same with the UMC(I'm on #10 in 2.5 years). Whoever makes these engineering decisions at Tesla is asleep at the wheel, and if it continues the company will fail. Not that complicated to understand, and even Tesla cannot fake reality for very long.

 

[omarsultan]

AFAIC, noise == failure. just as someone pointed out above, it is a lesser degree of failure. does or premediate a complete failure where you're totally stuck? i'm not sure, i dont think anyone knows. it is a bearing that gets worn...so plausible. Tesla just proactively replaces them while the noise is occuring but before the actual 'total failure' point. same difference to me. noise is still a type of failure.

You cannot assume that all DUs have the same failure mode. The specific example Elon used on the earnings call was a wiring bundle coming loose and creating a mechanical bridge between the DU and the frame.

 

[Al Sherman]

It shouldn't matter how you drive (as long it's not in some intentionally abusive manner like towing heavy trailers or doing hill climbs or something), but I wonder the same thing. I made it 32k miles on one and have gone about 28k miles on my second and am a pretty conservative driver (Lifetime Wh/mi = 305), and Jerry33 is still on his original at over 50k miles and is a serious hypermiler (lifetime Wh/mi ~280). Would be interesting to see a spreadsheet showing lifetime Wh/mi as a surrogate for driving style vs time to first (or beyond) DU replacements.

I'm not sure about the low mileage, or the driving style scenario. I'm not Jerry but my lifetime Wh/mi is 297 and I got a new DU (B series) in Sep of 2014 with 15k on the car. 1.5 years of driving.

 

[Max*]

I am far from a qualified electrical engineer but I've been told that the DU problem is electrical in nature and it appears that there is some sort of flaw in the build/implementation of the unit.
since there hasn't been a fixed found for this reoccurring noise all that tesla can do is to replace the DUs on an as needed basis.
IMHO as long as tesla supports us by "cheerfully" making the swaps, which alleviates the problem, this is just a bump in the road, albeit a huge bump.
nonetheless it is a far from fatal flaw, and many of us have driven many, many miles with the problem.
hopefully a fix can be engineered and soon we can look back and just chalk up this problem to growing pains that are inevitable in maturation of a revolutionary technology.

I can agree with what you said. It's a problem (call it whatever you want, failure, flaw, defect, etc.), and a permanent fix needs to be engineered.

 

[efusco]

This is the point of disagreement.
The sound IS normal, however, Tesla doesn't want that sound their.
.

Unless you have solid information to confirm that, I have to call that totally false. And yea, I'm a fanboi, but to excuse the loud abnormal whine or milling that we've experienced "normal" is against all logic. No properly functioning motor should develop that noise unless it is due to something changing abnormally within the mechanical structure of the motor itself--by definition abnormal even if you're wont to call it "failure". By the way Tesla has responded to these issues and based upon the number of outright DU failures we've seen documented it seems that Tesla also does not deem this "normal".

 

[flathillll]

The problem is they have had their gear/mech guys on the team to fix the problem while the problem is not mech per se

Tesla needs to either:

1) either ground the shaft with a brush (which would make it a service item)

2) use expensive non-magnetic ceramic bearings (which they did on the Roadster and have an other set of problems)

Improved flux shielding has already been implemented on newer motors

Sadly the motor designer was poached Atieva so he was not there to fix it (but even he might not have determined the root cause correctly)

Now he works for Facebook on the new solar wing. All he cares about is money.

In any case the problem will be fixed, but it has taken Tesla way too long to identify the root cause as they made the wrong assumption (as almost anyone who has not designed high power EV's would have done). Most motor designers have no experience in EV design where the peak to average power ratio is so high.

Lucky the drive unit assembly can be swapped in minutes like an old air cooled VW motor.

The Model 3 won't have this issue now that they have learned the hard way

 

[MsElectric]

Unless you have solid information to confirm that, I have to call that totally false. And yea, I'm a fanboi, but to excuse the loud abnormal whine or milling that we've experienced "normal" is against all logic. No properly functioning motor should develop that noise unless it is due to something changing abnormally within the mechanical structure of the motor itself--by definition abnormal even if you're wont to call it "failure". By the way Tesla has responded to these issues and based upon the number of outright DU failures we've seen documented it seems that Tesla also does not deem this "normal".

I agree. I'm not sure how anyone with a straight face can claim an abnormal milling noise to be not a defect.

If someone's car developed a milling noise, would they not want that fixed?

 

[AB4EJ]

Would we say that current Tesla owners (and persons like myself who are gearing up to buy one) are still early adopters? I seem to recall that when we started building the Mercedes M-Class (new product, new plant, new team, etc.), it took us quite a few years before the silly defects, failures, and high warranty costs came down. The M-Class (now called the GLE and other similar G-badges) is now a pretty solid product (but this is 20 years later). The question is: does Tesla have the kind of deep pockets and staying power that Daimler had, so that it can weather a difficult product start-up? A big challenge for Tesla is that it doesn't have a large product line where profitable, extremely good products can "subsidize" the cleanup of new, difficult models.

Also, remember that Tesla is engineering-driven- which means they are making engineering changes to a lot of things all the time. One would have to think this applies to improvements to the drive unit, since this has been a sore spot. If there is a real solution (fancy ceramic bearings), why would this not be on the top of the list of fixes?

 

[Only Trons]

Just had my first DU replacement. Have been hearing the "electrical whining" noise for several months and it has been increasing in volume. Tyco Rd Service Center listened to it, sent a recording to Tesla engineering, and was authorized to replace it. MS 85; delivered Apr 2013; ODO miles 29,739; avg Wh/mi since delivery is 297.

Looks like I received a "Q" unit. I don't know what the acronym "RC" means in the description .....

Anyway, absolute quiet drive home today after picking up the car from the SC.

 

[lolachampcar]

I really hate to add to threads like this, but -
Two friends that bought MS on my recommendation have had their drive units replaced and now my wife's second car is making noise. They are all in the 20K - 30K mile range. I can no longer say five cars with zero problems

 

[Jdcleary]

I have had 3 replacements as follows:
10548 miles on 8/29/2013 part 1002633-00-E
26455 miles on 5/27/2014 part 1025276-00-A
53640 miles on 6/25/2015 part 1025276-00-K
Last replacement was to cure a low speed high pitch whine that I couldn't hear (old age) but drove my wife crazy and she refused to take vacation until fixed.

 

[scottm]

This, I was going to add information along these lines to this thread if nobody else had..

The problem is they have had their gear/mech guys on the team to fix the problem while the problem is not mech per se

Tesla needs to either:

1) either ground the shaft with a brush (which would make it a service item)

2) use expensive non-magnetic ceramic bearings (which they did on the Roadster and have an other set of problems)

Improved flux shielding has already been implemented on newer motors

Sadly the motor designer was poached Atieva so he was not there to fix it (but even he might not have determined the root cause correctly)

Now he works for Facebook on the new solar wing. All he cares about is money.

In any case the problem will be fixed, but it has taken Tesla way too long to identify the root cause as they made the wrong assumption (as almost anyone who has not designed high power EV's would have done). Most motor designers have no experience in EV design where the peak to average power ratio is so high.

Lucky the drive unit assembly can be swapped in minutes like an old air cooled VW motor.

The Model 3 won't have this issue now that they have learned the hard way

Thank you flathillll

I was told similar. The milling sound has to do with micro-pitting of metal bearings as caused by high frequency high power transmission through them. Induced eddy currents of the massively powerful motor generating a lot of magnetic flux creates current in parts that don't need to have current in them. Like bearings. That chatter under load with power applied.

Why does the sound happen on applied power and not regen? Reversed role of the motor, reversed magnetic directions, reversed current flow... out a different path. The stationary casing of the motor, which is ground strapped...

Would strapping a rotor after the bearing has been compromised stop the milling sound once it had started?

Adding a brush wouldn't be so bad, even as a wear item, I bet you could get a very long lasting design and accessible from the exterior of the casing.