Parts for your 2018 Mitsubishi Asx-Oil seals

2018 Mitsubishi ASX oil seals — what they do and when to sort them

Oil seals absolutely are used on the 2018 Mitsubishi ASX. Technical references including the Mitsubishi Motors 2018 ASX/RVR Workshop Manual (engine, transaxle and driveline sections) and the Mitsubishi ASA electronic parts catalogue confirm factory-fitted seals at the crankshaft (front and rear main), camshafts, balance shaft (where applicable), transaxle/CVT case, driveshaft (axle) outputs and differential. These seals keep engine oil and transmission fluid where they belong while keeping grit out, so the ASX runs smoothly and reliably.

On the ASX’s petrol 4B-series engine and its manual or CVT driveline, oil seals serve a simple purpose: contain pressure-lubricated oil around rotating shafts. The front crank and cam seals sit behind the front covers, the rear main seal lives between engine and gearbox, the transaxle/CVT and differential output seals sit around the driveshafts. When a seal wears or hardens, oil weeps out, dropping fluid levels and potentially contaminating belts, clutches or rubber mounts.

Oil seals aren’t a scheduled replacement item, but they should be checked at every service. A good workshop will inspect for misting or drips during 10,000–15,000 km services. Common clues the ASX might need attention include:

• Oil spots under the car or a wet underside around the crank pulley, bellhousing, or driveshafts
• Burning-oil smell after a drive, or smoke from oil contacting hot exhaust areas
• CVT or transaxle fluid seepage at the axle stubs, sometimes with light shudder from low fluid

Replacement is straightforward for some seals and more involved for others. Axle seals are typically done with driveshaft removal and a fluid top-up. Front crank or cam seals usually require removing belts and covers and setting timing correctly. The rear main seal is a bigger job because the gearbox has to come out, it’s wise to address any clutch issues (on manuals) at the same time.

For longevity, use genuine or high-quality OEM-spec seals, fit them square with the correct driver, lightly oil the lips with the fluid they’ll run in, and inspect the shaft surfaces for grooves. After any seal work, refill with the correct engine oil or CVT/transaxle fluid and reset levels hot/cold as specified in the Mitsubishi workshop manual. If crankcase pressure helped cause the leak, a fresh PCV valve and a clear breather path keep the new seal happy.

Popular questions about 2018 Mitsubishi ASX oil seals

How often should oil seals be replaced on a 2018 ASX?
They’re not a time- or kilometre-based item. They’re replaced when they leak or if access is convenient during other jobs (for example, timing work or a clutch/CVT service). Regular inspections at each service are the go.

What are the most common leak points on the ASX?
Workshops most often see front crank and cam seals weeping, axle/output shaft seals at the transaxle or CVT, and occasionally the rear main seal. Condition, heat cycles and crankcase pressure play a role.

Is it safe to keep driving with a small oil seal leak?
Small misting might be monitored short-term, but any active drip should be fixed. Leaks can lower oil or CVT fluid levels, risk belt contamination, and escalate into bigger repairs if left too long.