Coolant Delete Plate for Large Drive Units – LDU

Large Drive Unit — Tesla Model S/X Coolant Bypass (Coolant Delete Plate)

Also known as a coolant bypass, this upgrade eliminates the factory rotor seal coolant path inside early Tesla Large Drive Units—a known weak point with near-universal failure over time that can allow coolant into the motor and inverter.  If your S/X is out of warranty and you want to extend drive-unit life, we install an aftermarket coolant bypass manifold / delete plate.  If symptoms are already present (noise, vibration, isolation errors), we can perform a full drive unit rebuild with a 1-year limited warranty.

Why these fail

• Rotor seal path — Coolant circuit through the rotor shaft depends on seals that harden, groove, or lose tension.
• Coolant ingestion — Once breached, coolant contaminates bearings, stator, and inverter power electronics.
• Escalation — Early signs (hum/whine, vibration, isolation faults) can rapidly progress to major drive-unit damage.

If the proactive DIY replacement path is unsuccessful, we offer solutions

• Coolant delete plate / bypass manifold — Removes the rotor seal coolant path entirely.
• Correct sealing & torque — Surfaces cleaned, sealant applied per spec, fasteners torqued and paint-marked.
• Health check — Inspect bearings, encoder, resolver, harness, and inverter cavity for any coolant evidence.
• Stator Repair — Our process includes resolving isolation faults in the stator windings caused by coolant ingress.
• Full rebuild option — For noisy or contaminated units; includes bearing/seal set and electronics remediation. 1-year limited warranty.

Gruber Motor Company — OTHER EV & Drivetrain Capabilities

Service & coverage

We install and repair LDU drive units.  Performed at our Phoenix facility by EV drive-unit specialists.  We road-test, scan for isolation faults, and validate under load after service.  Shipping/transport options available. Out-of-state customers welcomed.