MajorCommonTransmission

Mitsubishi Outlander: 4B12 Petrol CVT Belt Slip and Judder

4B12 Petrol CVT Belt Slip and Judder is a common transmission fault on the Mitsubishi Outlander on the 2006–2012 cars, and we rate it major. Putting it right costs $2,200 to $6,000 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 47 documented faults on the Mitsubishi Outlander.

Vehicle: Mitsubishi Outlander
Engine: 4B12
Years: 2006–2012
Fuel: petrol
Gearbox: cvt
System: Transmission

This page covers the Mitsubishi Outlander as a model. Some faults only affect particular engines or build years — enter a plate below to narrow the list to one car.

All Mitsubishi Outlander faults47 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph of the CVT belt and pulleys yet. We would rather show none than show a picture of a different part.

What goes wrong

The INVECS-III continuously variable transmission paired with the 4B12 2.4-litre petrol engine uses a push-belt running between variable-diameter pulleys. Degraded CVT fluid allows micro-slip between the belt and pulley faces, initially producing a characteristic judder felt through the drivetrain during light acceleration from rest and when the transmission is cold. As the fluid condition worsens or the belt sheave surfaces become scored, slip escalates into power loss under load and the TCM may store torque reduction requests. Without a fluid service interval being observed (Mitsubishi specifies fluid replacement at 40,000 km under severe use), internal wear progresses to belt and pulley replacement, a repair that typically costs more than the vehicle's market value.

What you would notice

Shudder or vibration through the drivetrain during light throttle acceleration from rest, most pronounced when cold
Flare in engine rpm without a corresponding increase in vehicle speed under moderate load
CVT warning lamp or transmission temperature warning illuminated during sustained low-speed use
Burnt or discoloured CVT fluid visible on the dipstick or during a drain

How to check it

Where to look. CVT transaxle beneath the engine bay, accessed from below the vehicle

Check CVT fluid condition — severely discoloured (dark brown or black) or burnt-smelling fluid indicates overdue service or internal wear. Road-test from cold with light throttle from standstill: any shudder or jerky engagement points to belt slip. Inspect the CVT cooler lines for leaks that cause low fluid level. If a workshop inspection is possible: Connect a scan tool and monitor CVT slip ratio and ATF temperature; elevated slip under normal load is diagnostic.

Parts involved: CVT belt and pulleys.

What it costs to put right

$2,200 to $6,000 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.

Ask the seller

“Has the CVT fluid ever been serviced, and at what odometer reading?”
“Does the vehicle shudder or jerk during gentle acceleration from a standstill?”
“Has the transmission warning light ever illuminated, or has any transmission-related fault code been stored?”

Now check the Mitsubishi Outlander you are actually looking at

Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.

Not sure what you would be paying for? See what a full KickTyres check includes.

Where this comes from

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.

Mitsubishi Outlander buyer questions

Is 4b12 petrol cvt belt slip and judder serious on a Mitsubishi Outlander?

We rate it major and common on the Mitsubishi Outlander. The INVECS-III continuously variable transmission paired with the 4B12 2.4-litre petrol engine uses a push-belt running between variable-diameter pulleys. Degraded CVT fluid allows micro-slip between the belt and pulley faces, initially producing a characteristic judder felt through the drivetrain during light acceleration from rest and when the transmission is cold. As the fluid condition worsens or the belt sheave surfaces become scored, slip escalates into power loss under load and the TCM may store torque reduction requests. Without a fluid service interval being observed (Mitsubishi specifies fluid replacement at 40,000 km under severe use), internal wear progresses to belt and pulley replacement, a repair that typically costs more than the vehicle's market value.

How much does it cost to fix on a Mitsubishi Outlander?

$2,200 to $6,000 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.

Which Mitsubishi Outlander years are affected?

Our research records this fault on the 2006–2012 Mitsubishi Outlander. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.