Toyota Noah: CVT (K112F) Belt Wear and Shudder

ZRR70 Noah models sold with the K112F continuously variable transmission (CVT) exhibit progressive belt and pulley wear, leading to shudder under light acceleration and slipping under load. Toyota issued fluid change intervals for this unit but many imported examples arrive in NZ with degraded CVT fluid that has never been serviced, accelerating belt and pulley face wear. The shudder is most pronounced at 20–50 km/h during gentle acceleration from low speed, caused by micro-slip of the steel push-belt across worn pulley faces. A CVT fluid flush with Toyota Genuine CVT Fluid FE can temporarily reduce shudder but does not reverse mechanical wear once groove patterns develop on the pulleys.

• Pronounced vibration or judder felt through floor and seat at 20–50 km/h during gentle acceleration
• Transmission slipping or flaring under moderate to heavy throttle above 80 km/h
• Whining or droning noise from transmission that varies with road speed
• Delayed engagement or clunk when selecting Drive from Park after overnight cold soak

1. 1

   Test drive at steady 30–50 km/h on light throttle — note any vibration or judder transmitted through the drivetrain.

2. 2

   Check CVT fluid condition via dipstick or fill plug: fluid should be red/pink and odour-free; brown or burnt fluid indicates neglect.

3. 3

   Ask for CVT fluid change history.

4. 4

   Inspect for any whine under load.

5. 5

   If shudder is present, budget for CVT rebuild or replacement unit rather than fluid-only treatment.

Parts involved: CVT belt and pulleys.

$2,200 to $5,500 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “Has the CVT fluid ever been changed — if so, when and with what fluid specification?”
• “Is there any vibration or judder felt during slow acceleration?”
• “Has the transmission ever been serviced by a Toyota dealer or specialist?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.