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The latest drive unit explanation

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JRP3

Hyperactive Member
Aug 20, 2007
25,238
74,235
Central New York
From the conference call:

There was like this one period of time where we had, I mean, it was like that was getting into the weeds, like we transitioned from manual, just before we transitioned to automatic grease injection into the spline of the large drive unit, we had variation in how much grease was put into the spline. And if not enough grease was put into the spline, it would have premature wear. That's, like, one example. But other than that, the large drive units have been great.

I don't know if that was referring to the Norway issue or another more recent problem.
 
So it seems like that's just another casual brush off, like drive unit issues are this blip on the radar. When the user feedback, at least on here, seems to be trending not if you will have drive unit issues but when. If it was just a matter of filling up the internals with the proper amount of fluid, why go through A-M number of revisions? I still believe that dual motor chassis are their way to reduce overall stress on a single drive unit and get the car to 200k miles where a failure/issue with either of them would be reasonable to expect.
 
I too caught the latest drive units are great comment. Normally when there are so many likes in a sentence from someone as straight forward as Elon, the person is searching for words that contain grains of truth while simultaneously avoiding putting their foot into their mouths (from personal experience, my feet do not taste good).
 
That quote explains the clunk, but what about the milling noise? Like posted above Elon is trying to skirt around the issue, granted it's just noise and not catastrophic failures in most cases.

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I would think the spline would be wet lubed by the gear oil in the unit, not grease. That means there must be an oil seal separating the spline from the gear case. In this video you can see the gear drive on the motor shaft that engages the gear on the drive unit, I don't even see a spline. :confused:

http://www-origin.teslamotors.com/nl_NL/videos/high-efficiency-electric-drive-unit
The spline can't be wet, because the rotor shaft is water cooled.
 
Elon also stated that they have changed their internal goal from a 200,000 mile drive unit to a million mile drive unit.

Next question... do any of you care that your drive units are internally rated by Tesla for only 200,000 miles? What about all of the talk about electric motors being far less complicated than an ICE engine, less moving parts, more reliable, etc., yet the DUs in circulation today will only last 200,000 miles? Seems like a low number to me. Anything to be concerned about?
 
Elon also stated that they have changed their internal goal from a 200,000 mile drive unit to a million mile drive unit.

Next question... do any of you care that your drive units are internally rated by Tesla for only 200,000 miles? What about all of the talk about electric motors being far less complicated than an ICE engine, less moving parts, more reliable, etc., yet the DUs in circulation today will only last 200,000 miles? Seems like a low number to me. Anything to be concerned about?

I care. I plan to keep the car for 8-10 years, that should put me close to 200k miles when I'm done with my Model S (we do about 20k miles a year, and have been doing more with the Tesla for whatever reason).

If that means the cost to fix/swap the DU after the warranty expires will be half the cost of the car, then that'll tank my resale value.

Now if my DU goes bad between now and then, and they swap it even once in the next 7.5 years, the 200k rating doesn't bother me one bit.

ETA: I agree with the poster above, if the MTBF is rated at 200k miles, that means it could last a lot longer than that.

ETA2: I'm assuming catastrophic failure, not service at 200k miles. If it's just a "tune-up" at 200k, then I don't care.
 
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Next question... do any of you care that your drive units are internally rated by Tesla for only 200,000 miles? What about all of the talk about electric motors being far less complicated than an ICE engine, less moving parts, more reliable, etc., yet the DUs in circulation today will only last 200,000 miles? Seems like a low number to me. Anything to be concerned about?

I have owned nothing but Hondas. Honda warranties its powertrains for 5 years 60k miles, but I have heard through unofficial channels that the design target is 10 years 150,000 miles before repairs are needed. A design target of 200,000 miles before service is perfectly acceptable to me.
 
I care. I plan to keep the car for 8-10 years, that should put me close to 200k miles when I'm done with my Model S (we do about 20k miles a year, and have been doing more with the Tesla for whatever reason).

If that means the cost to fix/swap the DU after the warranty expires will be half the cost of the car, then that'll tank my resale value.

Now if my DU goes bad between now and then, and they swap it even once in the next 7.5 years, the 200k rating doesn't bother me one bit.

ETA: I agree with the poster above, if the MTBF is rated at 200k miles, that means it could last a lot longer than that.

ETA2: I'm assuming catastrophic failure, not service at 200k miles. If it's just a "tune-up" at 200k, then I don't care.

I have owned nothing but Hondas. Honda warranties its powertrains for 5 years 60k miles, but I have heard through unofficial channels that the design target is 10 years 150,000 miles before repairs are needed. A design target of 200,000 miles before service is perfectly acceptable to me.

Thanks, there was no reference in the call if 200,000 was a MTBF number. Elon said "last 200,000 miles" and "last a million miles" based on what I heard during the call, but those aren't exact quotes. This is unfamiliar territory for me. If others aren't concerned, I probably won't worry about it.
 
I've been through at least 4 drive units, and the current one is exhibiting the same grinding/whining/milling noise the prior 4 did. I appreciate the fact that Tesla has replaced each one with no cost to me except for time. I've been told that it appears to be a bearing design issue, whatever that means. They were testing out the new drive units and I am supposed to get contacted once they start shipping them. This has been the only issue I've had with the car, and I really hope they address it as I would like to keep the car for at least 8-10 years as I've done with my last 3 cars.
 
I've been through at least 4 drive units, and the current one is exhibiting the same grinding/whining/milling noise the prior 4 did. I appreciate the fact that Tesla has replaced each one with no cost to me except for time. I've been told that it appears to be a bearing design issue, whatever that means. They were testing out the new drive units and I am supposed to get contacted once they start shipping them. This has been the only issue I've had with the car, and I really hope they address it as I would like to keep the car for at least 8-10 years as I've done with my last 3 cars.


P85?
 
I've been through at least 4 drive units, and the current one is exhibiting the same grinding/whining/milling noise the prior 4 did. I appreciate the fact that Tesla has replaced each one with no cost to me except for time. I've been told that it appears to be a bearing design issue, whatever that means. They were testing out the new drive units and I am supposed to get contacted once they start shipping them. This has been the only issue I've had with the car, and I really hope they address it as I would like to keep the car for at least 8-10 years as I've done with my last 3 cars.
Please report back on the new drive unit once you get some miles on it. Would love to hear confirmation of progress here.
 
Tesla's 8 year unlimited miles warranty is pretty amazing, so I'm not too worried about the DU. Others give 5 years and 60k miles limited. I'd be out of warranty on my drive train already with them. With my Model S I'm still covered for many years no matter how much I drive.
But a warranty is just a trust mechanism. Having issues with a car even under warranty makes you nervous about the quality of the car. I had my DU replaced 4 times. All under warranty and at no cost to me. Always received great service. But if I weren't a hard core believer in EVs and supporting Tesla for their amazing efforts, I don't know if I would be pleased with my car right now.
 
The solace I am taking away from the whole exercise is that this is Tesla's first drive unit, they will learn and it will be better moving forward. I'll keep this in mind all the way to the service center next week as I drop my wife's car off for a DU swap.