Ford HF35 (eCVT)

Ford's hybrid transaxle — in the Fusion Hybrid and the Lincoln MKZ Hybrid.

It is not a CVT in the belt-and-pulley sense, and that is the most useful thing on this page. There is no belt, no chain and no clutch pack: a planetary gearset splits the engine's output between the wheels and a generator, and two electric motors do the rest. The ratio varies because the motors' speeds vary, which is why it reads as a CVT to a driver and to a listing.

So the failure modes of every other CVT here do not apply. There is no belt to slip, no clamping pressure to lose and no launch clutch to judder. A shudder or a slip on one of these is not the transmission — it is far more often the engine, a mount, or the hybrid system's own transitions.

What does fail is electrical: the motor windings, the inverter, and the coolant loop that keeps them cool. The high-voltage system has its own cooling, and a hybrid-specific coolant service is real maintenance rather than an upsell.

Its mechanical parts are few and long-lived, which is why these reach very high mileages in taxi service — the strongest available evidence about the design.