Colour and Texture Have Changed
Fresh oil is golden and slick to the touch. After absorbing combustion residue it darkens and feels gritty when rubbed between your fingers.
The Engine Sounds Rougher
Degraded lubrication increases friction between components. The engine sounds coarser, especially on a cold start.
- Light knocking at low RPM
- Engine note feels heavier than usual
- Increased vibration at idle
Oil Level Keeps Dropping
Rising oil consumption indicates the oil is evaporating at operating temperature, or there is a leak. Both need attention.
The Oil Warning Light Comes On
The dashboard indicator is not an early warning. In many vehicles it illuminates only once oil pressure is already below the safe threshold. Do not delay inspection.
The Interval Has Passed
If your service record shows the interval has been exceeded, change the oil regardless of how it looks. Additive degradation is not always visible.