Drive unit failure

Drive unit failure

Our week old 3 had a drive unit failure. Quite astonishing for a new car, and embarrassing while you are stranded in the middle of the road halting traffic.
I thought these drive unit failures were the thing of the past, with old model S's.
Am I the only one? Anyone else have experience with these failures?
Tesla has been very accommodating/helpful with the replacement.
But can't help feel jaded, and fearful when taking it on long trips now.

spuzzz123 | 6 April 2018

This identical thread is also in this forum. Somebody really wants us to see this.

spuzzz123 | 6 April 2018

I meant to say the link you sent autotxer7 is also a standalone thread in this forum

Coastal Cruiser. | 6 April 2018

"Quite astonishing for a new car"

That is true a bummer tardi5shah. For what it's worth keep in mind that this is a completely new power train separate and apart from previous Tesla models.

It would be great if you could follow up in this thread with the specific of what component failed. Thank you and good luck with a quick repair process!

MilSpec | 6 April 2018

Drove mine for 3 days and now in service for 6 days and counting.

spuzzz123 | 6 April 2018

Is joeshah related to tardi5shah?

stevea137 | 7 April 2018

Indeed it would be great if we get a followup of what happened, and also a better description of how it failed and what the car did. We are all interested in the gory details.

We are interested largely because most of the others posting this failures have posted once and disappeared, never to be seen again.

stevea137 | 7 April 2018

Something we would really like to know is did the drive unit really fail, or did a sensor flip out and the computer get paranoid shut the drive unit down. For example, another person who had a "failed drive unit" error, was able to clear it by going into tow mode and back out or something like that.

carlk | 7 April 2018

I'm really glad there were only two drive unit failures the day when TSLA went up 20%. Just saying.

jordanrichard | 7 April 2018

The DU’s that you have read about with regard to the MS’s were 99.9999998 % of the time were replaced to fix a milling noise that originated from the original steel ball bearings in the motor. It was out of confidence that Tesla did the quickest thing and that was to swap out the entire DU versus dropping the DU, take the motor off, disassemble the motor to get to the bearings, replace them with the improved design with ceramic bearings and put it all back together.

Coastal Cruiser. | 7 April 2018

"We are interested largely because most of the others posting this failures have posted once and disappeared, never to be seen again."

Never to be seen again? Careful, someone may make a conspiracy theory out of that. ;>

Cclcal | 14 November 2018

ours just failed today, 2200 miles.
tried rebooting, resetting car, no luck.

Has to be mechanical, heard large clunking sound just before car died and lost all momentum. No drive no reverse available.

At Tesla now...

Coastal Cruiser. | 14 November 2018

From a pragmatic point of view, all the reports that I've noticed from owners who have had a broken drive unit received a full replacement unit from the gigafactory, where the motors are assembled. The SC receives the unit and performs a swap. Probably a time saver as the SC does not need to troubleshoot/repair a broken unit.

From a mechanical failure point of view I've been curious about what exactly the hell is breaking. The fact that this report has the speedometer reading jumped sans an actual increase of speed is telling, but of course not definitive. It infers that the break occurred after the point where the speedo sensor is installed. For a moment the motor's RPMs went up as the load was released from the wheels at the break point.

Where is the speedo sensor? Not sure if we have learned that yet from the various teardown videos. But in spite of scarce availability of photos for the internal components of the gearbox/transaxle, Ingineerix did video a component fitting over the end of the motor that has electronics for the motor controller to determine motor position. Given the simplification and parts reduction theme of the Model 3, plus the fact that the gearbox is a single-speed drive unit, the position sensor on the motor may well do double as a speedo sensor.

Of course that means the failure might be occurring anywhere at or after the helical gears the motor shaft connects to. But if you look at the photo Tesla released of the million-mile testing results, there does not appear to be a whole lot going there in terms of gearing. The Model 3 drive unit may be a much simpler design than, say, the Model S drive unit.

So the question remains.. what is breaking in this rather simplified drive enclosure. Is it a parts sourcing issue, or an assembly issue. Inquiring minds want to know.

(I'll bet a nickel on it being a supply line issue)

greg | 14 November 2018


description of the fault sounds like a broken axle [or whatever its called on the Model 3 - probably transfer shaft].

Exactly the same would happen if a RWD ICE broke its driveshaft [or more likely, the universal joint connecting the driveshaft to the gearbox broke/failed].

As most ICE's have the speedometer take off at the gearbox, breakage afterwards would see the "speed" increase for a little bit as reported by the speedometer even as the vehicle was slowing.

Yes and I'd bet one of the parts suppliers didn't make them strong enough for the torque load an EV applies to its wheels. Probably used to making parts for lower torque devices.

I'd bet Tesla is all over it though.

But as folks are finding, EV's and their drive trains cause subtle challenges all over the place - e.g. the "Winter tyres affecting regen" issue, supposedly due to the different tread pattern causing the traction control some issues.
No one would think of such things happening with an ICE. but the rulebook is being chucked out the window with EVs - Its a whole new world out their for all these parts suppliers. And some are clearly struggling to manage the difference.

Kikujiro | 14 November 2018

I had a friend who had a Audi A4 for about 5 months, and 8K miles and engine block cracked. Stuff happens.

Kikujiro | 14 November 2018

I have a feeling people are getting lead foot syndrome with these electric cars. Driving fast is fun but for god sake people, don't floor your car all the time. It's not good for your car and it's not safe. Just use it when you need it or when the conditions are safe.

Cclcal | 14 November 2018

that's great insight, I will definitely try to obtain as much detailed info as possible from service center.

kutoroff | 29 March 2019

Had my Model 3 for 3 weeks when the motor failed exiting the Interstate and found myself unable to move with traffic all around and a semi right behind. Estimate for delivery of the new motor is 17 days post incident. If it goes 3 days longer than that I could trigger the lemon law. This failure appears to be way more common than I would ever have expected and I've never lead footed the car or experienced an engine failure on an ICE vehicle, and yes they do happen. At least I have a Model S loaner, which by the way only makes me miss the Model 3 more. Only thing I really like on the S is the display of energy used and the running 30 minute average. That would be nice on the 3. I was loving it until then. It will have earn my love once I get it back.

ty.mccartney | 14 October 2019

I purchased my used 2013 S85 rear wheel drive with 79k miles in Feb 2019 and have been ecstatic, telling everybody who will listen how great EVs/Tesla is. I now have 89k miles on it. Two weeks ago my drive unit failed without much warning. The day before having to coast through an intersection because the DU stopped working, I was starting to accelerate in a parking lot and a violent shaking occurred before coasting to a stop. Besides that, I had no warning before the failure the next day. Anyway, it's still at the SC getting replaced under warranty. I'm grateful I still have 1.5 years left on the warranty but I'm seriously deliberating whether I will keep my 2013 S85 once I get it back from being repaired. Prior to purchase and up until 2 weeks ago I thought I had only the battery to worry about for large expenditures. I just replaced the passenger side window regulator 3 weeks ago for $400 and I realize the door handles will run $1k for replacement but I was willing to roll the dice. Sure, I can handle battery degradation and assumed a complete battery failure was not probable but I was unaware of drive unit failures unit I saw many forum posts about DU failures after mine failed. Perhaps the estimated $6k DU cost replacement isn't a big deal for some Tesla owners but I'm not prepared for a DU failure once my warranty expires in April 2021.

I suppose the Model S (and perhaps other models) are just not designed to be long term vehicles. I envisioned keeping my S85 for the next 10 years however the DU failure has probably changed that plan. I will follow up here if I get miraculous news from the SC about resetting the DU unit warranty ( which is unlikely) but I wanted to post about my experience. I truly hope Tesla fixes this issue moving forward because I really want to be all in with Tesla.

fazman | 14 October 2019

Things break. You fix it and it probably won’t break again. You are a pioneer if you own any EV... so you may have to pay to play if you keep your tesla outside of a warranty.

Car insurance can also cover mechanic breakdown at a cost spread out over many months (just like a factory back insurance plan).

The door handles on the model S are a known issue and it was resolved with a new $1 gear that can be DIY’ed. I also believe another issue is some contact/connecter which costs a few dollars can also be DIY’ed at the same time to resolve any weaknesses in the door handle presenters. Usually if you have reached a high age of miles/time than this door handle issue has already been addressed on your car (go check the service history to be sure).

I drive all my ICE cars to high mileage and well outside of any warranty. I do pay to play in repairs to keep my cars road worthy and safe. Sometimes, the maintenance costs more than the car is worth on the used market. But a refreshed car with FCPEuro parts (backed by a lifetime no questions return policy)is a great value in not having a car payment. I see car payments as perpetual insurance, depreciation, interest, sales tax, and high registration cash grabs. Even if you spent $6k on Drive Unit. That part would have a warranty and you would make up the saving from FUSC on your cpo tesla. Couple with all the savings from doing next to no maintenance on the EV.

RedPillSucks | 15 October 2019

@ty.mccartney one gets this issue with many (most?) car manufacturers.
My Nissan 240z aluminum (head valve covers??) warped at 90k miles. The repair people said that this happens to most of the same engine types at about the same mileage. My Honday Oddesy transmission failed at 110k miles. The Honda repair person indicated that this was normal and almost didn't cover it under warrentee (100k miles) until I got Honda service on the phone and also found out there was a recall. My Saturn Outlook had transmission issues at 90k miles. These are established brands. I get that Tesla needs to do better (EVs have fewer moving parts so less to break). They're a new company and they'll get there.

rxlawdude | 15 October 2019

@ty.mccartney "door handles will run $1k for replacement."

Um, where did you pull that number from? It is patently false. Most of the time the gear that breaks can be replaced for a total of <$300; a complete new mechanism is ~$600.

jordanrichard | 15 October 2019

rxlawdude +1. You are quoting old prices

A new door handle, driver's side ran me $540. As for the window regulator replacement, I would have to look at my records, but I am fairly certain I paid less than that.

As for that $6K for a drive unit, if true that is for the whole DU, but the DU is in itself 3 separate components, bolted together. Service has the ability to service the DU's. The original "problem" with the DU's was a milling noise and initially the quickest way to fix it was to swap out a DU altogether even though it was just the bearings in the motor. Starting I think in the summer of 2015 the service centers were able to do the bearing repair, which mean removing the motor itself. My whole point here is you are most likely quoting a whole DU replacement when the fact it is not the whole DU that fails.

joe.lynn.atp | 15 October 2019

Stock must be up again today. A six month old M3 thread hijacked to complain about a used Model S problem?

lbowroom | 15 October 2019

Because no Internal Combustion Engine has ever had a failure at 89,000 miles and needed replacing. Therefore if one electric motor fails at 89,000mi, they will all fail? How do you argue with logic like that?