Understanding automotive fluids- what they do and when to replace them?


Car servicing is an essential aspect of owning a vehicle. It involves regular checks and maintenance of various parts, including automotive fluids. These fluids play a crucial role in keeping your car running smoothly and efficiently. Engine oil is perhaps the most critical fluid in your car’s engine. Its primary function is to lubricate moving parts, preventing friction and wear causes damage. In addition to lubrication, it helps cool the engine by carrying heat away from critical components. You should check your engine oil level regularly using the dipstick provided in your car’s engine bay. Your oil needs to be changed if it is low, dirty, or discolored.

Brake fluid

Brake fluid is responsible for transmitting force from your foot on the brake pedal to the brake calipers applying pressure to stop the wheels. It also acts as a lubricant for various components within the braking system. Use only the recommended brake fluid type specified by your vehicle manufacturer. Brake fluid absorbs moisture over time and contributes to the corrosion of metal components within the braking system. Therefore, you should replace your brake fluid every 2-3 years, or earlier if your vehicle manufacturer recommends it.


Coolant (also known as antifreeze) helps regulate engine temperature by dissipating excess heat through a radiator after circulating through various components such as hoses and water pumps. If you notice any signs of overheating, including steam coming out from under the hood or a dashboard warning light indicating a high temperature reading then the coolant is low and needs immediate attention otherwise too much heat buildup causes serious damage like warping heads or pistons seizing up. If the temperature gauge is rising but there are no steam or warning lights, then the most likely cause is a failing thermostat, which needs to be replaced. Other possible causes include a failing water pump, a faulty radiator fan, or a blocked radiator. In any case, it is best to have the cooling system fully inspected and maintained by a qualified mechanic.

Transmission fluid

Transmission fluid is responsible for lubricating moving parts within the transmission and torque converter, helping to transfer power from the engine to the wheels. Car servicing Exeter also acts as a coolant, preventing overheating of components within the transmission. According to the make and model of your vehicle, you should change your transmission fluid frequently. Transmission fluid replacement intervals vary greatly from vehicle to vehicle. However, generally speaking, you should replace your transmission fluid every 50-100k miles or every two years.

Power steering fluid

Power steering fluid helps in the smooth operation of your car by transmitting force from the steering wheel input to the hydraulic pump assists in easy steering. It provides lubrication for various components within the power steering system. If you experience trouble turning the steering wheel or hear a noise like a whining noise, there could be an issue with power steering that needs immediate attention. Check manufacturer recommendation for replacement interval as it varies depending on make and model.

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