6 Essential Car Fluids and How to Check Them

Knowing how and when to check car fluids—like brake fluid, transmission fluid, and motor oil—is crucial for the long-term health of your vehicle. Essential car fluids have a wide range of important jobs, from regulating engine temperature to keeping your windshield streak-free. We recommend that you keep an eye on these six:
- Engine oil
- Brake fluid
- Engine coolant
- Transmission fluid
- Power steering fluid
- Windshield wiper fluid
This guide from the Fisher Honda service team covers what every driver in Louisville or Broomfield should know about when and how to check essential fluids in your car, and why it’s important to do so.
How to Check Essential Fluids in Your Car
All six of these essential car fluids should be checked on a regular basis and replaced as needed or at intervals recommended by your manufacturer. Let’s take a closer look at how and when to check car fluids like windshield wiper fluid, brake fluid, motor oil, and engine coolant.
Note: before checking the level of any essential car fluids, wait until the engine has had time to cool for at least 30 minutes before opening the hood!
Motor Oil
- Purpose of motor oil: Prevents friction between engine parts and regulates engine temperature.
- When to change motor oil: Every 7,500 to 10,000 miles or every six months.
- How to check motor oil: Find the dipstick underneath the hood. Insert it into the oil reservoir and check the level and consistency of the oil.
Brake Fluid
- Purpose of brake fluid: Transfers movement and force from the brake pedal to the braking system.
- How often to replace brake fluid: Every 30,000 miles or two years.
- How to check brake fluid: The fluid level should reach the marking on the side of the clear brake fluid reservoir underneath your car’s hood.
Engine Coolant
- Purpose of engine coolant: Optimizes temperature in your vehicle’s cooling system and engine.
- When to replace engine coolant: Every 50,000 miles.
- How to check engine coolant: The fluid level should reach the marking on the side of the engine coolant reservoir underneath your car’s hood.
Transmission Fluid
- Purpose of transmission fluid: Ensures fast and smooth gear shifts.
- How often to replace transmission fluid: Every 30,000 to 60,000 miles.
- How to check transmission fluid: Remove and re-insert the transmission fluid dipstick into the reservoir. Pull it out and observe the level of fluid. Check that the color of the fluid is a translucent dark red color. If you have a sealed transmission, you’ll need to bring your car to a Broomfield-area service center.
Power Steering Fluid
- Purpose of power steering fluid: Ensures proper function of the power steering hydraulic system, which multiplies the force you exert on your steering wheel.
- When to replace power steering fluid: As needed, when your vehicle is difficult to steer or the power steering system needs frequent service.
- How to check power steering fluid: Find the reservoir under your car’s hood marked with a steering wheel or the words ‘power steering fluid’ or it might be a steering wheel symbol. Make sure the fluid reaches the marked level.
Windshield Wiper Fluid
- Purpose of windshield wiper fluid: Increases efficacy of your windshield wipers for clearer glass.
- When to replace windshield wiper fluid: As needed, when no fluid comes out of the sprayers on your windshield.
- How to check windshield wiper fluid: Open the hood and find the reservoir with a windshield washer symbol on the cap.
Learn More About Essential Car Fluids with Fisher Honda
If you have questions about how to check essential fluids in your car or other DIY car care topics, we’re happy to help! Contact our service center to speak with a technician today. Looking to buy high-quality new windshield wiper fluid or brake fluid near Longmont? Order parts, accessories, and auto maintenance supplies online or make your purchase at our service center in Boulder.
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