Description

EVC Tesla “Holy Grail” LDU eDrive Repair Kit | Complete Motor & Gearbox Rebuild Solution

The ultimate Tesla Large Drive Unit mechanical repair solution, engineered by EV Clinic R&D and proven through 1,209,000 km of real-world operation.

The EVC Tesla Holy Grail LDU eDrive Kit is a comprehensive professional rebuilding solution for Tesla’s first-generation Large Drive Unit (LDU), combining electric motor bearings, reduction gearbox bearings, premium ceramic rotor bearings, oil seals and an advanced graphite rotor coolant seal.

Developed through years of EV Clinic research, failure analysis and real-world remanufacturing experience, the Holy Grail Kit is designed to address the critical mechanical components associated with premature LDU failure.

This is not simply a bearing replacement kit. It is part of a complete, field-tested LDU remanufacturing solution.

1. Proven Through 1,209,000 km of Real-World Driving

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<title size=”2xl” color=”success” tabularNums>1,209,000 km</title>
**Documented LDU Holy Grail road-test milestone**
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Most rebuilding kits are marketed based on component specifications, manufacturer claims or laboratory testing.

EV Clinic has documented a real-world Tesla Large Drive Unit operating for approximately 1.209 million kilometres following its remanufacturing intervention.

This achievement reflects not only replacement components, but the complete EV Clinic repair methodology, including mechanical restoration, correct assembly, component evaluation and long-term operational validation.

The documented vehicle accumulated its mileage under real driving conditions, demonstrating the long-term potential of properly remanufactured electric drive units.

Read the full case study:

Tesla Endgame: The King of 145 Years of Automotive History

The mileage is a documented result for a specific rebuilt LDU and does not constitute a guaranteed service life for every installation or kit.

2. Complete Kit Contents

The EVC Holy Grail Kit includes mechanical components for both the induction motor and reduction gearbox.

8 Bearings: Motor + Gearbox

6 conventional bearings:

• 6207
• 6208
• 6309
• 6308
• 6310
• NU2207

2 premium ceramic rotor bearings:

• 2 × 6007 Ceramic

The ceramic rotor bearings are intended for the electric motor rotor assembly, while the remaining bearings cover the relevant gearbox and drive unit bearing positions.

Advanced Sealing Components

• 1 × Graphite rotor coolant seal
• 1 × Rotor oil seal
• 2 × Half-shaft output oil seals

Oil seal dimensions:

• 44x67x10 mm
• 36x67x8 mm
• 30x55x8 mm

Optional Components

• 2 × Rubber motor mount bushings

Select the required configuration before ordering.

Related references:

• 6008779-00-D
• 1002666-00-A

• UH5322-E, UH5322E, BB1-3793, 6007-2RZTN9/HC5C3WT, 6008779-00-D, 1002666-00-A, 1002633-00-U, 1002633-01-U, 1025598-01-U

These references are provided for component identification. Confirm compatibility with the specific drive unit revision before ordering.

3. Why the Holy Grail Kit Is Different

Engineered Around Real Failure Analysis

The Tesla Large Drive Unit is a highly integrated system combining a powerful AC induction motor, a reduction gearbox and a liquid-cooling system.

Although replacing bearings may appear relatively straightforward, long-term reliability depends on much more than installing new components.

Critical factors include:

• Correct rotor and gearbox bearing installation
• Rotor shaft and bearing seat condition
• Rotor coolant sealing integrity
• Mechanical alignment and bearing preload
• Gearbox wear and gear contact condition
• Contamination control during assembly
• Stator insulation condition
• Proper lubrication and cooling system integrity

The Holy Grail Kit is developed around EV Clinic’s practical understanding of these failure mechanisms.

Advanced Graphite Rotor Coolant Seal

Coolant intrusion into the Tesla LDU electric motor is one of the most destructive failure mechanisms encountered during drive unit repairs.

Once coolant contaminates the motor cavity, it can contribute to corrosion, insulation degradation, bearing damage and costly secondary failures.

The EVC Kit includes a dedicated graphite rotor coolant seal as part of its mechanical rebuild solution.

Unlike solutions based solely on bypassing or deleting a coolant circuit, the EVC repair philosophy focuses on restoring the drive unit while retaining its intended cooling functionality.

Our objective is not to hide the failure mechanism. Our objective is to repair the drive unit correctly.

Seal performance depends on correct installation, shaft surface condition, mating components and cooling system integrity.

Premium Ceramic Rotor Bearings

The kit includes two ceramic rotor bearings for the electric motor.

Ceramic bearing elements offer electrical insulation and material performance characteristics that can be advantageous in high-speed electric motor applications.

Proper bearing selection, mounting tolerances, lubrication, temperature management and rotor condition remain essential to achieving reliable performance.

Complete Motor and Gearbox Coverage

The Holy Grail Kit enables professional workshops to service the major bearings and seals of the LDU motor and reduction gearbox in a coordinated rebuild.

This reduces the need to source multiple individual components and supports a more systematic repair process.

Developed by EV Repair Engineers

EV Clinic is an independent electric vehicle research and development laboratory specializing in the diagnosis, reverse engineering and remanufacturing of complex EV components.

The Holy Grail Kit is supported by actual LDU rebuilding experience, dedicated procedures and engineering knowledge gained from real-world failures.

4. Common Tesla LDU Failure Symptoms

The following symptoms may indicate problems involving the motor bearings, gearbox, coolant sealing system or electrical insulation:

• Whining, humming or buzzing sounds during driving
• Grinding or rumbling noises from the rear drive unit
• Unusual vibration under acceleration or regenerative braking
• Coolant leakage or unexplained coolant loss
• Coolant contamination inside the motor
• Deteriorating high-voltage isolation resistance
• Tesla HV isolation fault messages
• Metallic particles in gearbox oil
• Damaged rotor bearings
• Corrosion or damaged motor components discovered during disassembly

Important: The kit addresses mechanical components. It cannot repair every electrical, inverter, stator winding, rotor or housing failure. Additional restoration may be necessary following diagnosis.

5. More Than a Repair Kit: EV Clinic Remanufacturing Expertise

Successful LDU rebuilding may require operations beyond bearing and seal replacement.

EV Clinic also provides specialist services, including:

Stator Rewinding

Professional stator winding restoration is available for qualifying units, including B2B wholesale arrangements.

Rotor Repair

Selected damaged rotor components and rotor teeth can be assessed for restoration.

Mechanical Inspection and Rebuilding

Rotor shafts, bearing seats, gearbox components and other critical mechanical parts require inspection before assembly.

EVC Academy

Professional training and technical procedures are available for qualified technicians performing Tesla LDU repairs.

The Holy Grail Kit supplies mechanical rebuilding components. Specialist repair services and training are separate unless explicitly included in the purchased offer.

6. Vehicle Compatibility

Designed for compatible first-generation Tesla Large Drive Units used in:

• Tesla Model S
• Tesla Model X

Applicable versions depend on the installed Large Drive Unit generation, configuration and revision.

Important: Compatibility must be confirmed using the original drive unit identification and part number, rather than the vehicle model or production year alone.

Not suitable for Tesla Small Drive Units (SDU), Model 3/Y drive units or other incompatible eDrive architectures.

7. Professional Installation and Technical Requirements

The Tesla LDU is a complex electric drive unit requiring specialized equipment and professional rebuilding experience.

Replacing bearings and seals without correcting the underlying mechanical or electrical fault can result in premature failure, additional damage or compromised high-voltage safety.

Before assembly, inspect all relevant mechanical components, including rotor shafts, bearing seating surfaces, gearbox housing, gear contact surfaces and coolant sealing interfaces.

All components must be installed according to suitable technical procedures, with correct tolerances, mechanical adjustments, lubrication and validation testing.

First-time LDU rebuilders are strongly advised to complete EVC Academy training before attempting installation.

Technical resource:

EVC Academy: Tesla LDU Repair Manual

8. ⚠️ HIGH VOLTAGE SAFETY WARNING

DANGER: HIGH VOLTAGE ELECTRICAL SYSTEM. RISK OF FATAL ELECTRIC SHOCK.

The Tesla Large Drive Unit is part of a high-voltage propulsion system. Improper isolation, disassembly, testing or reassembly can result in electric shock, severe injury, burns, fire or death.

Mandatory safety requirements:

• Work must be performed exclusively by appropriately qualified EV technicians with the required high-voltage certification, including HV Level 3 or equivalent where applicable.
• Before removing or disassembling the drive unit, follow the vehicle manufacturer’s approved high-voltage shutdown and isolation procedure.
• Disconnect the relevant low-voltage service disconnect or service loop and 12V supply as specified in the applicable procedure. These actions alone do not establish electrical safety.
• Prevent accidental re-energization using appropriate lockout and identification measures.
• Observe all manufacturer-specified capacitor discharge times.
• Verify the absence of hazardous voltage at the prescribed measurement points using appropriately rated and verified test equipment.
• Use approved high-voltage PPE, insulated equipment and suitable workshop safety procedures.
• Never touch exposed HV connections, inverter terminals or internal electrical components before safe isolation has been verified.
• Never energize or operate a partially assembled drive unit.
• After repair, perform the applicable insulation resistance, sealing, electrical safety and functional validation tests before returning the vehicle to service.

WARNING: A switched-off vehicle or disconnected 12V battery does not mean the high-voltage system is electrically safe.

Unauthorized or unqualified attempts to repair the Tesla LDU can cause serious injury and irreparable damage to the drive unit.

EV Clinic recommends installation only by trained and certified EV repair professionals.

9. Warranty and Repair Responsibility

The Holy Grail Kit is intended for professional use.

EV Clinic does not provide a repair-kit warranty without the required technical training, as stated in the product conditions. Applicable statutory consumer rights remain unaffected.

The successful outcome of an LDU rebuild depends on the condition of the original drive unit, correct diagnosis, workmanship, installation procedures and testing.

The documented 1,209,000 km road-test milestone demonstrates the potential of EV Clinic’s complete remanufacturing approach. It is not a mileage warranty or guarantee that identical performance will be achieved in other vehicles.

10. Sustainability Through Engineering

Replacing a complete electric drive unit because of repairable mechanical damage creates unnecessary expense and material waste.

EV Clinic’s approach is to retain and restore serviceable components wherever technically and economically feasible.

Through advanced remanufacturing, component-level diagnostics and specialized repair engineering, the useful lifetime of complex EV powertrains can be extended significantly.

Don’t just replace bearings. Understand the failure. Rebuild the complete drive unit. Validate the repair.

EVC TESLA HOLY GRAIL LDU eDRIVE KIT

8 bearings | 3 oil seals | Graphite coolant seal | Optional motor mounts

Complete motor and reduction gearbox coverage.

1,209,000 km documented real-world LDU performance.

Developed by EV Clinic R&D, Croatia.

EV Clinic is an independent repair and research organization and is not affiliated with or endorsed by Tesla, Inc.