Toyota K-Series CVT (Prius/Hybrid) · Toyota/Lexus · Expert rebuild service since 1987. Lifetime warranty. Free diagnostic.
2004–present Toyota Prius (K110/K111); 2012–present Toyota Prius C (K111/K112); 2016–present Toyota Prius Prime (K113); 2015–present Toyota Yaris Hybrid (K112); all Toyota hybrid powertrains
| Configuration | Power Split Device — eCVT (no conventional gears; torque split by planetary gearset + two motor/generators) |
|---|---|
| Gear Ratios | Continuously variable through electronic torque vectoring; no fixed gear steps |
| Fluid Type | Toyota ATF Type WS (or dedicated hybrid transaxle fluid) |
| Fluid Capacity | 3.0 qts (transaxle fluid, separate from inverter coolant) |
The K-series eCVT uses two motor/generators (MG1 as generator, MG2 as drive motor) on the same planetary gearset. MG bearings wear at high mileage (150k+) causing whine and eventually affecting drive capability.
Symptoms: High-pitched whine increasing with vehicle speed; not present at idle; hybrid system warning
The hybrid inverter (separate from but integrated with the K-series transaxle) fails and triggers shutdown of the hybrid system. Not a mechanical transmission failure but affects the eCVT's operation.
Symptoms: Hybrid system warning; limited propulsion; P3000-series hybrid codes
Lack of transaxle fluid service allows planetary gearset wear from inadequate lubrication.
Symptoms: Whine from transaxle; vibration; fluid discoloration
The K-series eCVT requires Toyota hybrid specialist equipment and high-voltage safety training for MG1/MG2 work. We service the planetary gearset lubrication system and fluid. Motor/generator repairs require Toyota-certified HV technician.
Change transaxle fluid every 60,000 miles. The K-series eCVT is extremely durable when maintained — many Prius reach 300,000+ miles without major transaxle work.
The Prius uses a Power Split Device — an eCVT (electronic CVT) based on a planetary gearset with two motor/generators. There are no traditional gear shifts; ratio is controlled electronically.
Extremely durable — 250,000–350,000+ miles is common. The eCVT has very few moving parts vs a conventional automatic.
We handle fluid services and planetary gearset inspection. Motor/generator and high-voltage work requires Toyota-certified HV technicians with proper safety equipment.
Toyota ATF Type WS for the transaxle fluid section.
A speed-dependent whine in a Prius often indicates MG bearing wear. This requires HV-certified diagnosis. We can do initial assessment but MG repair goes to an HV specialist.
Free diagnostic, written estimate, lifetime warranty. Chicago's K110/K111/K112/K113 rebuild specialists since 1987.
