P85D LDU failure leak past rotor coolant delete by QCC

[utahski500]

Wish I had noticed issues with large drive unit earlier, but now out of warranty issue. 2/15 P85D 70988 miles.
$8022 to replace rear drive due to “moisture past RDU cover”. I am guessing it is the coolant past rotor seal failure. My questions: can I ask for my drive unit from Tesla once they replace it? Has anyone done the coolant delete fix from QC charge ($599)? Did Tesla ever have recall or fix for said issue? I honestly can’t believe there hasn’t been a class action. Thanks for your replies.

 

[ucmndd]

questions: can I ask for my drive unit from Tesla once they replace it?

Yes although they will add a hefty core charge if you do.

Did Tesla ever have recall or fix for said issue?

No.

I honestly can’t believe there hasn’t been a class action.

What is the claim? They’ve dutifully replaced them as required during the warranty period. It would be pretty hard to argue an 8 year unlimited mile warranty is somehow lacking. Producing a mechanical part with a design flaw is not inherently against the law.

 

[utahski500]

Yes although they will add a hefty core charge if you do.

No.

What is the claim? They’ve dutifully replaced them as required during the warranty period. It would be pretty hard to argue an 8 year unlimited mile warranty is somehow lacking. Producing a mechanical part with a design flaw is not inherently against the law.

I guess…don’t buy one out of warranty. Thanks for the resale value tesla…

 

[utahski500]

Yes although they will add a hefty core charge if you do.

No.

What is the claim? They’ve dutifully replaced them as required during the warranty period. It would be pretty hard to argue an 8 year unlimited mile warranty is somehow lacking. Producing a mechanical part with a design flaw is not inherently against the law.

The claim would be they know there is an issue, that can be fixed, but no fix has been offered and no preventive measures have been suggested even at owners expense to prevent major damage and immense cost and loss of value as well as good will. I was a huge supporter, helped sell a few Teslas to friends. Now, Not so sure. I have never owned an ICE that didn’t get 100k+ on engine and transmission.

 

[howardc64]

Has anyone done the coolant delete fix from QC charge ($599)? Did Tesla ever have recall or fix for said issue?

I heard QCC's first batch of parts are due in in Jan 24. Need one myself.

Tesla's parts catalog briefly listed their coolant delete part a few months back. Inquired availability. Tesla said no and the part has since disappeared from catalog. Pretty simple part. We can hope for availability in the future (maybe the class action but that'll probably take quite awhile). Here is my post when I found the part + PN.

Tesla Large Drive Unit (LDU) Motor Teardown and maintenance - Page 17 - openinverter forum

Some people have tried to mod existing manifold. Doesn't look too easy. Need to press out long coolant tube + metal working skills/tools.

 

[MP3Mike]

Did Tesla ever have recall or fix for said issue?

Rumor is that the latest "U" revision of the LDUs from Tesla have a "fix" for the issue. But I would think it might introduce cooling issues. (It was intended to cool the rotor, can you just bypass it with no negative implications?)

I honestly can’t believe there hasn’t been a class action.

I honestly can't believe that people think every failure should result in a class action. (And that companies are responsible for keeping something working essentially forever.)

 

[howardc64]

Rumor is that the latest "U" revision of the LDUs from Tesla have a "fix" for the issue. But I would think it might introduce cooling issues. (It was intended to cool the rotor, can you just bypass it with no negative implications?)

Yes, lots of chatter on this with those that have rebuilt the LDU. Here is a post, a bunch posts before and after

DIY Tesla Drive Unit Repair

So looking at these posts from QC Charge and the U-revision/manifold delete from Tesla, they seem to be narrowing in on the solution to the “when not if” LDU problem. I am still on my original LDU on my 12/2015 build P90D, but when I pulled my speed sensor there was moisture present (not rusty...

teslamotorsclub.com

The coolant circuit for rotor has a 5mm outlet restriction and very low pressure so amount of flow and therefore heat removed is probably isn't huge.

QCC part page also list discoloration of rotor on their part website. I have rebuilt the LDU and seen the rotor. There seems to be some kind of coating on it looking like clear coat paint. Had my rotor shaft repaired (where the coolant seal rides) with flame metal spray process, also saw discoloration afterwards. I believe the repair required a 200C bake to cure a sealer to seal the porous holes from flame metal spray process. Anyhow, I'm not sure these discoloration are from the metal discoloring (would require really high temps) or whatever coating is on there.

COOLANT DELETE Tesla Large Drive Unit

Don’t let a leaking rotor seal in your Tesla motor cause expensive damage! All of the cars with the Tesla “Large Drive Unit” (formerly the “570A” motor) have the fatal flaw of leaking coolant (cars listed below). This leaking coolant issue will short out the stator (field windings), seize and...

qccharge.com

Finally, Roadster motor design is largely same as MS but has only 1/3 power and no rotor coolant cooling. Did some study but inconclusive

Tesla Large Drive Unit (LDU) Motor Teardown and maintenance - Page 19 - openinverter forum

Probably answer is nobody knows and you'd hope Tesla did some due diligence. Was original coolant cooled rotor over design? Or is the coolant delete expecting failure but higher longevity than the remans?

There are numerous weak points on the LDU design that results in gradually deterioration not addressed on Tesla remans which unfortunately doesn't inspire confidnece. So far, I've seen the following

• Tesla reman process seems to not refinish the rotor shaft back to original spec based in inspection of my reman LDU during rebuild (Some aftermarket rebuilders do) These shafts and seal material require very precise finish to work well. Not refinishing the rotor shaft is a likely cause for rapid failures on the remans and also the reason to use a less robust seal on remans as more robust seal require well finished shaft.
• LDU gearbox has 3 shafts and 1 shim. Reviewing similarly design Chevy Bolt gearbox (All EV motors need a 9 or 10 to 1 3 shaft gearbox, pretty simple compared to any manual or auto transmission) rebuild documentation shows 6 shims (2 for each end of each shaft) and a very traditional shim sizing measurement process. Seems Tesla is expecting no variation from wear, reman disassembly and bearing change (pressing etc). Seems quite optimistic or maybe just inexperienced.

 

[utahski500]

I heard QCC's first batch of parts are due in in Jan 24. Need one myself.

Tesla's parts catalog briefly listed their coolant delete part a few months back. Inquired availability. Tesla said no and the part has since disappeared from catalog. Pretty simple part. We can hope for availability in the future (maybe the class action but that'll probably take quite awhile). Here is my post when I found the part + PN.

Tesla Large Drive Unit (LDU) Motor Teardown and maintenance - Page 17 - openinverter forum

Some people have tried to mod existing manifold. Doesn't look too easy. Need to press out long coolant tube + metal working skills/tools.

Thank you, how do you know if you will get a rev ‘U’ unit from Tesla?

 

[howardc64]

Thank you, how do you know if you will get a rev ‘U’ unit from Tesla?

Rev U released recently so don't know how much older rev inventory in the logistics pipeline. It will say on your quote. Might want to confirm with SC personnel if you want Rev U. Might even ask if that is the coolant delete revision (they might not know?) Don't know if they are willing to take a pic for you before install to confirm.

Here is invoice on Rev U and older Rev (T)

Need Help: Rear Drive Unit Replacement $6k

Get a remanufactured one from Tesla thats what i did when mine went out last month. It's much cheaper and it has the same 4 year warranty Tesla gives on a new drive unit if they were to install it for you. I'm wondering what the additional $1500 is going to for my 2014 60 quote? Mine shows...

teslamotorsclub.com

Need Help: Rear Drive Unit Replacement $6k

Need help and advice on this situation. A couple days ago, I got the "Vehicle May Not Restart" error message. Got the car towed to local service center and they diagnosed the issue as the rear drive unit. They said they will only replace and don't have the ability to open up the drive unit to...

teslamotorsclub.com

Rev U will look like this on one end with the new coolant delete manifold

Tesla Large Drive Unit (LDU) Motor Teardown and maintenance - Page 19 - openinverter forum (top pic)

Older revs look like this instead

https://teslamotorsclub.com/tmc/attachments/img_3003-jpeg.874736/

 

[utahski500]

Tesla would not do a core exchange, for
Any price. The approved quote was $6000 LDU, they switched that to a Rebuilt one without asking and lowered price to $5200

 

[howardc64]

Tesla would not do a core exchange, for
Any price. The approved quote was $6000 LDU, they switched that to a Rebuilt one without asking and lowered price to $5200

Can post the quote? reman LDU prices seems to have dropped slightly compared to the past.

 

[utahski500]

Can post the quote? reman LDU prices seems to have dropped slightly compared to the past.

Good news, it is the U rev.

 

[howardc64]

Good news, it is the U rev.

BTW, most people's guess is no firmware change with coolant delete and QCC mentions nothing on their aftermarket part. Any firmware update indicator on invoice? Think you can check with SC to confirm?

 

[airborne spoon]

I got the U unit installed last month it works no idea if it's different at all internally lol but time will tell I suppose.

My stock 2014 drive unit lasted for 190k miles and failed a few months ago and I got it replaced out of warranty. But then that remanufactured unit failed after a month or 2 and then I got the U model under warranty which is where I'm at now.

 

[utahski500]

I should probably explain how this all started. I got an error message on my car stating that it required service and it may not restart. I waited a few days and a weekend and a few more days went by and then it told me it would not restart and it shut down the computers. That’s when I towed it to the dealer and they told me it was my lower drive unit. I assumed it was a short or bad ground inside and researching it found that there are problems with the LDU.
On my way home from that service replacing LDU and they had also replaced the battery. I got the same error message. I went to get into my car in the next morning it was already totally dead and trying to charge the battery or jump did not start the computers. I had it towed back to the service center where they found a bad coolant heater and high voltage cable to the front motor, now the vehicle is fixed. The additional cost was $1500.
Since they did not allow me to take the core or buy it, I will never know if the LDU actually had any issues at all.

 

[silverp85+]

Yes although they will add a hefty core charge if you do.

No.

What is the claim? They’ve dutifully replaced them as required during the warranty period. It would be pretty hard to argue an 8 year unlimited mile warranty is somehow lacking. Producing a mechanical part with a design flaw is not inherently against the law.

You do know a warranty is just a security blanket that should not be used 5 times for the same part, right? get your nose out of Elon's ass, please! Name 1 car in your lifetime that has had 5 engines replaced. They normally get repaired

My P90D LDU has been replaced 5 times (on the 6th) and the warranty just ended. It seems Tesla is just replacing with the same units and they know the warranty will expire and the owner will start paying and get pushed to buy a new car. A good attorney can use the data and extend the warranty to a lifetime or make Tesla buy the cars back.

 

[howardc64]

My P90D LDU has been replaced 5 times (on the 6th) and the warranty just ended. It seems Tesla is just replacing with the same units

Hope your 6th is recent and got rev U that eliminated the problematic leaky rotor cooling. Of course will have to wait for longevity data on the hotter running rotor.

But yeah. What an expensive mess. If assume 250k LDU replacements (probably more counting % LDU cars and # of swaps, I’m on #3 and doing own rebuild for #4 and coolant delete #5 in < 80k miles) Maybe most @ $2k+/ea for Tesla under warranty. $7k/ea for customer out of warranty. Gets to $1B pretty quick.

10+ years to solve this design problem suggest far more focus on future revenue growth than solving existing product problems. Tesla PE ratio is 10x Toyota and 2-3x social media company average. Probably tells most of the story

 

[mr_hyde]

I’m concerned what happens to the stock when the narrative really starts to change about the longevity issues. Right now they can just excuse the legacy cars but I’ve seen at least three 2019 and newer HV failures this week. When the 2nd gen packs that were supposedly ‘better’ start to fail at similar rates as the original packs, it will be a harder tale to spin.

 

[Fgpalmer71]

I've also recently had the revised U version of the LDU recently installed out of warranty. Had mine installed on 12/27 and was told it had a coolant bypass at the SC. Seems to work fine....it does feel a bit down on power compared to the old one in my opinion though.

 

[howardc64]

I've also recently had the revised U version of the LDU recently installed out of warranty. Had mine installed on 12/27 and was told it had a coolant bypass at the SC. Seems to work fine....it does feel a bit down on power compared to the old one in my opinion though.

If it is down on power, then maybe Tesla loaded firmware to reduce the LDU power. Another alternative is higher temperature picked up by thermal sensor limiting the power output but I don't see how that can be instant after powering up a cold car. I'm guessing detuning LDU is similar/same as not demanding as much power through the accelerator. But don't know for sure. Does the invoice say any firmware flashing? To really know for sure, one would need

- Use ToolBox3 to snoop before and after -U LDU to see if any LDU inverter controller firmware changes (don't know if TB3 can see this much detail)
- Gather LDU temp sensor data before and after -U in same condition to compare (I think 4-5 total shown in MCU's coolant loop display in diag mode ( link ). 1 in stator, 1 in coolant entry to inverter, 1 in coolant exit from inverter, 1 or 2 on inverter phase boards)

Anyway, not easy for aftermarket / DIYer to learn for sure as Tesla publish no info.