Under repair (2024/04/21).

Table of Contents

Disclaimer

All work you do on your car is at your own risk. Please check the EV High Voltage Safety section below before working on your car's high voltage system.

EV High Voltage Safety

EV high voltage circuits are deadly, so familiarize yourself with safety before starting. Generally, the most important step is to disconnect the battery pack from outputing high voltage to the rest of the car. All EVs have easily accessible method for this. It is designed for emergency services personnel in case of accidents involving EVs. Recommended readings:

Required DIY Skill Level

A LDU rebuild job is an advanced DIY skill level. Much online rebuild info is from peope with access to good machine shop level equipment. It is possible for mid level DIYer who has done things like change transmission valve body, removed CAMs etc. But likely well beyond light DIYers. LDU rebuild is of similar complexity as say a clutch or automatic transmission torque inverter replacement job. Some additional nuances are:

EV Builders Beware

EV builders making a custom car with this LDU are likely to experience highly corroded shaft surface for mating the coolant seal. The shaft likely contains rusted pits after cleaning which requires metal surface repair. The shaft is probably not stainless steel and corrosion is likely if the LDU has been sitting idle for long periods because. LDU has likely been idle for quite some time, for example in a wrecked car sitting in salvage lots for long periods, and/or the LDU pulled and stored for long periods. Coolant will likely leak out if it hasn't already, air and oxygen enters the cooling system and rust the shaft exactly where coolant seal will mate to the shaft. The shaft surface has to be recovered to prestine condition for proper sealing. The best thing to do for long term LDU storage is to probably remove the coolant manifold If it wasn't just fully rebuilt with all coolant vacated from the system. It is maybe also not good to have seal sitting idle on coolant shaft for very long periods (months to years) because seal failure seems not only develop with mileage but also with just time.

Rebuilders

There are very few rebuilders in US so statistically will be far away from the customer. Generally, even independents such as 057 (NC USA) and Gruber Motors

(AZ USA) send LDU rebuilds to unknown third parties. It is expected that the rebuild business ramps up significantly as 2015 Model Ss will start coming off

8 year unlimited mileage drive train warranty. So the "next" LDU issue after warranty will be on customer's dime.

TMC Repair Shop Directory

QC Charge (CA, USA)

A well known LDU rebuilder is QC Charge (QCC) in Southern California. QCC does high volume of LDU rebuilds and have added a fair amount of modifications to reduce collateral damage (bearing damage and fry the inverter electronics) with this LDU design where the coolant leak is basically unavoidable over time.

A QCC rebuild includes: (source: TMC)

Cost in 2022 was about $2800 if you ship the LDU to/from their shop. And ~$4500 if you drop off the car there. Need to add the shipping charges to both cases. In Johan's case (mid 2022) it was $750 for 480 mi one-way Sacramento --> QCC, so roughly $1.56 per mile. So that would be $1500 for a return trip.

EV's Republic (CA, USA)

Recently another rebuilder was added: EVsRepublic.com/services/model-s/drive-unit

Failed attempts (Northern CA, USA)

Near the epicenter of Tesla development and manufacturing, i.e. Northern California, Johan was referred to independent shops that were the best bet (mid 2022).

None of these shops do LDU rebuilds: LusciousGarage | CarStar | A1 Body Shop | East bay Collision center | Dynamic Autoworks | EV4UNow | MakeMineElectric

Tesla Service Center (SC)

In most cases, cars with failed/failing LDU will have no choice but to go to a SC as other rebuild options require shipping cost and time delays. Tesla's LDU replacements cost is rumored to vary wildly. Actual quotes of $4800 and ~$750 install (depending on regional hourly rates) exist for MS85 (source) and P85 (source source). But have also heard of verbal quotes for $6k + $5k install (probably can't be right). QC Charge has noted prices seems to vary wildly since Tesla replacement is their competition. A possible reason for the wildly varying prices could be Tesla's own price fluctuation or their app based service communication solution. The app's chat communications have multi hour delays on each text and seemingly attended by not very automotive knowledgeable people. Along with frequent mistakes and probably a changing corporate price sheet for diagnostic fee. Was quoted $450 diag fee just to look at a wet speed sensor out of warranty in which a picture was provided in advance and mid aero shield already removed. But all this falls on deaf ears with whoever is on the other side of the chat line. Anyway, the app communication inaccuracies and frustration level can be a huge deterrent to those seeking cost effective solutions such as a DIYer. So it's a scenario that produces much hearsay and strong negative feedback. Tesla's replacement units does not include any collateral damage mitigation modifications and use the same old failure prone seal with high collateral damage. However, it can be done at your local SC and comes with 4 year 50k mile warranty.

General LDU information

Affected car models

The folllowing car models have this motor (location of motor in patenthesis):

Tesla provided 8 year unlimited milage warranty on the drive train. Most owners have had the LDU replaced 2-3 or even more times during these 8 years. After this period, the customer has to pay for swaps or rebuilds. Cost is $7k+. Thats when customer screams bloody murder. The majority of the failure may be related to the seal coolant leak and the collateral damages.

Number of affected cars

LDUs came with all RWD Model S and Performance Dual Motor Model S through ~2020. Through end of 2014, None-performance dual motor and MX used a different smaller drive unit (SDU) which is oil cooled with less leakage problems. Tesla delivered 57k MSs worldwide. 107K cars were delivered in 2015 (mostly MS, MX started selling in 9/2015) So roughly 75k cars have LDUs and at least two thirds of those are probably in the US. When factoring in a 5 year lifecycle per LDU before replacement, that is 40 LDU replaced daily worldwide.

pg 4 of the 2014 annual report outlining 57k cars sold to date

pg 32 of the 2015 annual report outlining 107k cars sold worldwide in 2015

In US, largest market in 2015 is CA, then FL, TX, WA, IL, NY and NJ | source

LDU specifications

To date, Tesla is not adding a weep hole to reduce seal leak collateral damage like flushing the grease out of the rotor bearings and damaging the inverter electronics. Since Tesla no longer manufactures cars with this LDU, there is probably no longer a high volume tooled factory to produce LDUs at the lowest cost. Tesla likely has multiple contract rebuilders on multiple continents. It seems unlikely they can dramaticaly reduce replacement LDU price.

Credits

Key forum information repositories:

Key information contributors: