MajorCommonFluid Leaks

Mitsubishi Lancer: 4G63T Crankshaft Rear Main Seal Oil Leak (Evo VII–IX)

4G63T Crankshaft Rear Main Seal Oil Leak (Evo VII–IX) is a common fluid leaks fault on the Mitsubishi Lancer on the 2001–2007 cars, and we rate it major. Putting it right costs ≈A$740 to ≈A$1,660 at independent workshop rates, shown as an approximate guide in Australian dollars. 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 39 documented faults on the Mitsubishi Lancer.

Vehicle: Mitsubishi Lancer
Only on: Evolution
Engine: 4G63-T
Years: 2001–2007
Fuel: petrol
Gearbox: manual
System: Fluid Leaks

This page covers the Mitsubishi Lancer 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 Lancer faults39 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph of the Clutch yet. We would rather show none than show a picture of a different part.

What goes wrong

The crankshaft rear main seal on the 4G63T is a known service item that hardens and begins weeping oil onto the flywheel and clutch disc by 100,000–150,000 km. When the seal leaks, oil contaminates the clutch, causing clutch slip, judder, and premature clutch failure. Because the seal is accessed by removing the transmission, the job is labour-intensive and is often deferred. Many Evo imports arrive with the leak already present but undisclosed.

What you would notice

Oil staining on bellhousing and clutch area
Clutch slip or judder with no apparent clutch wear
Burning smell from clutch under moderate load
Oil drips from between engine and gearbox on driveway
Black oily residue on top of transmission housing

How to check it

Where to look. Rear of engine block at crankshaft exit, behind flywheel

Inspect the joint between engine block and transmission bellhousing with a torch for oily residue or black staining. If visible, this strongly indicates rear main seal leak and possible clutch contamination. Factor in cost of clutch replacement at the same time as seal replacement since transmission must be removed for both.

Parts involved: Clutch.

What it costs to put right

≈A$740 to ≈A$1,660 at independent workshop rates, shown as an approximate guide in Australian dollars. That is for this job on its own, not for the car.

An estimate, converted to Australian dollars, 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 any oil leak been noticed at the back of the engine or gearbox area?”
“When was the clutch last replaced, and did it show oil contamination?”
“Has the vehicle ever had a rear main seal replaced?”

Now check the Mitsubishi Lancer 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 still has money owing on it, has been written off or reported stolen, what kms it showed in past sale ads, whether it has had accident repair claims and what it is worth today. That comes from the official records for that plate. Enter the plate and its state for the A$17.90 Vehicle Check, or the full history from A$24.99.

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 Lancer buyer questions

Is 4g63t crankshaft rear main seal oil leak (evo vii–ix) serious on a Mitsubishi Lancer?

We rate it major and common on the Mitsubishi Lancer. The crankshaft rear main seal on the 4G63T is a known service item that hardens and begins weeping oil onto the flywheel and clutch disc by 100,000–150,000 km. When the seal leaks, oil contaminates the clutch, causing clutch slip, judder, and premature clutch failure. Because the seal is accessed by removing the transmission, the job is labour-intensive and is often deferred. Many Evo imports arrive with the leak already present but undisclosed.

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

≈A$740 to ≈A$1,660 at independent workshop rates, shown as an approximate guide in Australian dollars. 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 Lancer years are affected?

Our research records this fault on the 2001–2007 Mitsubishi Lancer. 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.