Symptoms
Shuddering when pulling away or under light throttle, engine speed rising without matching acceleration, a whine that changes with road speed, or a delay before the car moves.
Likely cause
The belt and pulley surfaces rely on a fluid engineered for that specific transmission. Degraded or wrong-specification fluid reduces the friction the system depends on. Heat accelerates the process, which is why towing and stop-start traffic come up in the reports.
How should it be checked?
Ask what fluid went in and when. CVT fluid is not interchangeable between manufacturers, and the service interval is frequently shorter than owners expect.
How can you check it yourself?
From a standstill, accelerate gently and hold a steady light throttle. A shudder that feels like driving over rumble strips is the symptom to notice.
The question to ask the shop
When was the CVT fluid last changed, with which specification, and has the transmission ever been reprogrammed or replaced?