My car (Hyundai Santro) engine's original oil intake capacity is 3 liters. However, i have observed that it has reduced this capacity over the last 2, 3 drain intervals. Now its maximum intake capacity is 2.5 liters, anything poured more than that will be shown on the dip stick way above full mark. Question is, what can be the reason ?? sludge build up ??
Car has been maintained well (at least since i owned it). Its drive is smooth, acceleration is good till 100km/hr. After that its hard to accelerate. Max it goes is till 120 km/hr.
a brief profile/history:
Hyundai Santro Club 2005.
Odometer : 92k km. (with me since 82k km)
Oil Brand: Shell Helix HX5 (used since i purchased car 10 months back)
Oil grade: SAE 10W-40, API= SG
Oil type: mineral
Drain interval: 3000 km & OEM oil filter (air filter changed every 2nd oil change)
Oil consumption : 1 liter per 1 drain interval (topped-up all along.)
Fuel type : CNG (90%) / Petrol (10%)
Fuel economy: good on CNG /poor on petrol. (CNG: 20 km/kg, Petrol: approx 10 km/liter)
Problem: Engine is accommodating half-a-liter less engine oil (i,e 2.5 L) than its actual capacity 3 liters.
Experts... please comment.