15W-40 by Mobil I am using.
I was thinking the same. Asking for an overhaul then it must be neh?
A guy once told me, engine oil may mixed with fuel. This can be happened?
also I have noticed fuel consumption is low from recently. it does around 8-10 kmpl in colombo.
One more thing, Once I start the car in the morning it wont go even i accelerate. Have to keep the car for around 5 minutes to warm up in parking gear. But in low gears and revers gear this never happens.