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What Your Transmission Fluid Color Means

pouring transmission fluid into vehicleThe transmission in your car is essential in getting you moving. While your engine creates the power, the transmission is used to send that power to the wheels. Just like your engine, your transmission requires fluid to create pressure, reduce friction, prevent overheating, and keep internal components clean. Most fresh, clean transmission fluids are a bright red color but when that color begins to change from red to maroon to brown, should you be concerned? What does it mean when your transmission fluid is brown? We’ve got the answers to help you understand why you should pay attention to the many colors of your transmission fluid, the condition it’s in, and when it’s time to visit a service center.

The color of the transmission fluid in your vehicle can clue you in as to the condition of your transmission and provide subtle warnings of when something needs attention. To check the transmission fluid, you’ll need to locate the transmission dipstick, remove it, and wipe it clean with a paper towel or rag. The color of what’s left behind is an indication of the transmission fluid’s condition as well as the overall health of your transmission. Many modern vehicles today are no longer equipped with transmission dipsticks. Instead, you’ll need to take your vehicle to a repair center where a transmission professional will inspect the fluid level through a special plug found on the side of the transmission.

Is Transmission Fluid Red?

Condition: Excellent

Red, transparent fluid means that the fluid is new or like-new. Check your fluid regularly and be sure to have regular maintenance services, such as transmission flushes often to keep this fluid bright red and full at all times. By doing so, you greatly reduce your chance of future transmission issues.

Is Transmission Fluid Light Brown?

Condition: Good

Light brown and somewhat transparent means the fluid is acceptable but it is important to ensure the transmission fluid is flushed at the proper intervals. If fluid hasn’t been changed or flushed in over 50,000 miles, it’s time to schedule a flush. Continue to check the fluid regularly and monitor it making sure the color doesn’t get darker.

Is Transmission Fluid Dark Brown?

Condition: Serious

Cloudy, dark brown transmission fluid means it is old and contaminated. It’s likely no longer able to provide adequate lubrication which puts your transmission at risk for wear and damage to internal components. Dark brown fluid also indicates the internal temperature of the transmission is operating higher than normal, which can result in overheating, and failure. Don’t wait; get your vehicle over to a transmission professional for immediate assistance.

Is Transmission Fluid Dark Brown or Black?

Condition: Poor

Nearly black or black transmission fluid means the fluid is old, very dirty, contaminated, and if paired with a burnt toast smell, has oxidized. At this point, your transmission is telling you something is wrong. If your transmission is showing signs of slipping or hesitation, repair or replacement may be in order. Having maintenance services on the transmission at this stage is futile and could actually make things worse. Seek help by having the vehicle towed to a transmission professional promptly.

Is Transmission Fluid Foamy?

Condition: Serious

Foamy, bubbly, milky, or thin looking transmission fluid is a sign that coolant or water has mixed with the transmission fluid. Often this occurs due to a leak within the cooling lines or cooler of the radiator. Coolant leaks in the transmission prevent the transmission from receiving sufficient lubrication to moving parts. Additionally, chemicals in the coolant can cause serious damage to the transmission. To resolve this, the leak will need to be identified and repaired, and the transmission filter and fluid should be removed and flushed out. In more severe cases, a transmission rebuild may be in order.

Extend the Life of Your Transmission

By performing transmission maintenance, you can prevent overheating, improve gear operation, and fuel efficiency. Transmission flushes remove old, dirty fluid and are replaced with the new, clean fluid made specifically for your transmission. Your transmission will run cooler and vital components such as gears, clutches, and bearings will be better protected. Plus, a flush helps to clean the transmission by removing contaminants and sludge that has accumulated within the transmission. Once you have a transmission flush, you’ll feel the difference, too. The fresh fluid will ease friction and you’ll notice a difference because you’ll have a smoother and more consistent shift from gear to gear.

Call Upon the Transmission Expert

Transmissions are one of the most vital components of your vehicle’s operation. Protecting your transmission with maintenance will not only ensure your transmission lasts longer, but you’ll also be able to prevent costly rebuilds or replacements. The Transmission Experts at Sun Auto Service can help guide you on the recommended maintenance for your transmission as well as check your transmission fluid to determine its condition. Our ASE Certified Transmission Technicians are equipped with the knowledge, expertise, and equipment to perform maintenance services as well as complicated repairs for all makes and models of cars and light trucks. We guarantee all our work in writing and include an incredible warranty with each service or repair. To have your transmission fluid checked or flushed, schedule an appointment with the experts at Sun Auto Service!