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Drive unit failure/problem posts decreasing - reliability going up?

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Elon Musk is on record back in November (I think) saying that the current drive units are more reliable than the problematic early units. Also I don't notice as many posts about drive unit problems.

Is it just me or is this issue fading from the front pages of the forums?
 
I intend to give a full update post about this, as I have had my fair share of drive units. However, I will spoil that a little and say "yep, they've gotten better". My last two units lasted about a little less than a year and 20,000 miles before succumbing to milling and clunking. Both of those were Rev "A" drive units. My current drive unit is a Rev "M". I don't have a year on it quite yet, but just broke over 20,000 miles and it is still working flawlessly. I intent to give a more in depth post when I reach the full year milestone.
 
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I've had three, with my most recent being sometime in/around November. Hopefully I won't have anymore, they've been good about it, but I like my car vs getting a rental every 4 months to swap my motor

When you say 3, do you mean three actual failures, as in stranded you in traffic 3 times? Because if you're simply referring to a swap due to noise/milling/balloon/clunk, that's not the same thing.

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My own anecdotal evidence, as well as the frequency of reports on this forum, would have me thinking that reliability has gone up significantly as well.
 
Remember that many cars sold since late 2014 are D models. Other than the P85D/P90D, all other D models (70D, 85D, 90D) use only the smaller drive units.

To date, I don't believe I've seen a single report of a failed smaller drive unit, only the large ones. Part of that is because they're new -- the oldest smaller drive units in the field are a maximum of 16 months old. But even with that, not seeing a single post about a small drive unit failure in 16 months leads me to believe that the small drive units may in fact be more reliable.
 
Remember that many cars sold since late 2014 are D models. Other than the P85D/P90D, all other D models (70D, 85D, 90D) use only the smaller drive units.

To date, I don't believe I've seen a single report of a failed smaller drive unit, only the large ones. Part of that is because they're new -- the oldest smaller drive units in the field are a maximum of 16 months old. But even with that, not seeing a single post about a small drive unit failure in 16 months leads me to believe that the small drive units may in fact be more reliable.

Good observation - I hadn't noticed that.
 
That's awesome. My late 2014 has started making drive unit noises at low speed, drives fine but it's getting louder (kind of a ticking/milling noise? can't exactly describe it). It also whines a lot more than it used to.

I have a service appointment set up and I'm hoping for a replacement. Good thing they're getting better now.
 
I get a hum at 65-70 that is probably only noticeable to me. I don't know if I have the milling sound, as I really don't know what that sounds like. I've seen/heard the videos, but I really can't make out the sound. The car drives perfectly normally with about 18.5K on it. Original unit.
 
When you say 3, do you mean three actual failures, as in stranded you in traffic 3 times? Because if you're simply referring to a swap due to noise/milling/balloon/clunk, that's not the same thing.

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My own anecdotal evidence, as well as the frequency of reports on this forum, would have me thinking that reliability has gone up significantly as well.

I've had three swaps due to noise or a weird issue. 11K miles of my own on a 70k mile car.

First replacement was the clunk noise. Very prevalent, I knew something was wrong before I even signed up to these forums to read about these issues. Got a swap with no questions asked. Infact, I didn't even expect a swap, I was told it was happening.

Second replacement was a weird sticking when going from park to drive. I noted the times and asked the service center to look into it. The master tech suggested a swap again.

Third replacement was a variable loss of power when attempting to accelerate from a stop. Sometimes I would roll backwards into parking stubs while in reverse due to loss of power as well. Noted times, brought it in, suggested swap again.

So I am on my third due to my pro activeness of noticing issues. I have never been stranded. So if that's what this thread is about, then I don't have a vote.
 
It maybe like with chronic pain sufferers that get tired of complaining all the time some of us also get tired of complaining about things that go wrong with our model S. Just a thought.

Honestly does it matter if the car has stranded you and it's had to be swapped out or its been a noise that should NOT be there and has to be swapped out? Either way they had to be swapped out.
 
When you say 3, do you mean three actual failures, as in stranded you in traffic 3 times? Because if you're simply referring to a swap due to noise/milling/balloon/clunk, that's not the same thing.

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My own anecdotal evidence, as well as the frequency of reports on this forum, would have me thinking that reliability has gone up significantly as well.


This sounds familiar ... isn't there an entire thread discussing what constitutes a "failure?":biggrin:
 
I started this thread some time ago to poll users on drive unit replacements. If you have had a drive unit replacement, it asks when your car was produced. I felt this would be the best way to tell if the units were getting better over time.
To date, there have been 99 reports of failure and only 2 for cars produced in 2015. Most of the failures have been in cars produced in 2013 and early 2014. When you consider that there have been many more cars produced later in 2014 and 2015, the reduction in failures is even greater.
From this poll I think we can say that drive units are getting better.
Drive unit replacement - getting better? - View Poll Results
(If you have had a drive unit replaced and you have not voted in this poll, please add your experience.)
 
Remember that many cars sold since late 2014 are D models. Other than the P85D/P90D, all other D models (70D, 85D, 90D) use only the smaller drive units.

To date, I don't believe I've seen a single report of a failed smaller drive unit, only the large ones. Part of that is because they're new -- the oldest smaller drive units in the field are a maximum of 16 months old. But even with that, not seeing a single post about a small drive unit failure in 16 months leads me to believe that the small drive units may in fact be more reliable.

From what I can tell, very few replacements in the past have been from motor failures--most are from issues in the reduction gear area or are related to bearings. And most items reported as "failures" have actually been replacements due to noise. I'm not minimizing that issue--it is certainly a valid issue and it is right for Tesla to replace those units--but there haven't been a large number of cases where a driver is stranded on the side of the road from drivetrain failures, that I can tell.

As for why it's more common on the larger motors, I think this is likely because the larger motor produces significantly more torque, so there are more stresses on the components. My feeling is that there were issues through the end of 2014 or the beginning of 2015, and most of those have now been sorted out.

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Honestly does it matter if the car has stranded you and it's had to be swapped out or its been a noise that should NOT be there and has to be swapped out? Either way they had to be swapped out.

Well, not really--but three sounded like a lot, if they were actual failures. IMHO there's a big difference in severity between a problem that strands you on the side of the road, versus a noise that is just bothersome. Both should be fixed, but one is more severe than the other. I think what partly skews the results is that because the drive unit is so modular, Tesla opts to swap out the drive unit because it's cheaper and faster than trying to replace a specific component. So that tends to make the issues appear more drastic than they really might be.
 
I had one making milling noises replaced a while back at around 20K. It was the service center tech that made the call as the whirring sound wasn't on my list of big issues on a 2yr inspection. No failure or performance issues I could detect, it worked fine, just wasn't silent.

The new unit was dead silent and has stayed that way ever since. Fingers crossed.

3Q 2013 car.
 
Take this how you will since we know messaging can be a bit different from service center to service center, but when I was in Arizona over New Year's and helped my injured Model S-owning cousin take his Feb. 2013 car in for service (regular service, but it's also got the drive unit milling noise), the Scottsdale service team told us that they COULD put a new DU in the car, but it would likely start doing the same thing after around 20k miles. They instead put my cousin on a list for when a new, totally redesigned DU would arrive at the service center after Fremont finishes it. He didn't give exact dates, citing that Fremont was busy getting the X out the door, but thought it would be early in the New Year.

Anyone heard anything similar?
 
Take this how you will since we know messaging can be a bit different from service center to service center, but when I was in Arizona over New Year's and helped my injured Model S-owning cousin take his Feb. 2013 car in for service (regular service, but it's also got the drive unit milling noise), the Scottsdale service team told us that they COULD put a new DU in the car, but it would likely start doing the same thing after around 20k miles. They instead put my cousin on a list for when a new, totally redesigned DU would arrive at the service center after Fremont finishes it. He didn't give exact dates, citing that Fremont was busy getting the X out the door, but thought it would be early in the New Year.

Anyone heard anything similar?

Started noticing the milling noise in my Late Sep 2014 P85 @ around 16K miles a couple months ago. SC didn't seem too alarmed by it. Now at 17.5K and will be going to SC in 1.5 weeks for other issues and have them check it out first hand.

Will see if their response is consistent....
 
The only thing that worries me is that someone on the forum said that the milling noise was a symptom of a drive unit failure later down the road. The milling noise on my car has gotten much worse the last week or so and I'm worried that I'll have a DU failure before my scheduled service visit more than a month from now.