What type of fluid typically leaks if oil is dark brown and has a burnt smell?

When oil appears dark brown and has a burnt smell, it is indicative of motor oil that has degraded due to high temperatures and the accumulation of contaminants. Motor oil is designed to lubricate engine components, manage heat, and keep the engine clean by suspending dirt and debris. Over time and with exposure to excessive heat, the oil undergoes oxidation, leading to a darker color and a burnt odor, revealing that it is no longer functioning effectively.

The presence of these characteristics suggests that the oil has likely reached the end of its service life and may require a change. Recognizing these signs is crucial for maintaining engine health and performance.