2026-09-15
Lexus IS 250/300h/350 Engine Oil Leak Diagnosis & Repair Malaysia
Common IS 250/350 oil leak points at high mileage: valve cover gaskets (both banks of the V6 — replace both simultaneously for), front crankshaft oil seal, and oil filter housing O-ring. Small leaks typically appear at 100,000–150,000 km. The IS 300h's 4-cylinder is less prone to leaks. Address leaks promptly to prevent oil from contaminating engine mounts and spark plug wells.
IS Oil Leak Sources
- Valve cover gaskets: common seepage on 2GR-FSE/2GR-FE at 100,000 km+ — minor leak, not urgent but repair before it reaches hot exhaust components
- Oil filter housing O-ring: oil drips at filter area — replace O-ring, not the whole housing
- Rear main seal: seepage at 150,000 km+ on high-mileage IS — repair during timing chain or clutch work to save labour