Motor Oil & Transmission Fluids

Automotive fluids help keep your vehicle running like new

The fluids in your car are essentially its lifeblood, and your vehicle's components need different fluids to function as intended. They course through your vehicle and need to be clean to let your car, truck or SUV operate at peak performance. This means checking the fluids on a regular basis and changing them (or having a trusted auto shop do the job) when the time comes to refresh everything. If you like taking charge of car maintenance yourself, Walmart has all the fluids, filters and tools you need to keep your car running smoothly. You can save money doing it yourself, especially with our Every Day Low Prices. Here's what your car needs when it comes to fluids.

Motor oil and oil filters

Maintaining the motor oil in your vehicle is one of the most important things you can do to ensure your safety while driving, and doing so could potentially extend the life of your vehicle. Motor oil lubricates the many moving parts in your vehicle's engine and absorbs the heat that the movement of those parts produces. All of this causes the oil to break down after a few thousand miles, requiring you to change it and the oil filter. The type of filter you choose depends on what car you drive and the type of oil you use for it.

The types of oils available include conventional, which is the type most vehicles can use; full synthetic, which is chemically engineered to have fewer impurities and better properties, making it best for high- and low-temperature performance; synthetic blend, which is a mixture of conventional and synthetic oil that has added protection against oxidation; and high mileage, which is ideal for vehicles that are several years old or have more than 75,000 miles on their odometers. Motor oil is rated by its viscosity, with a higher number indicating a higher viscosity. Most oils have two numbers; you might see oils labeled with "5W-30" or "15W-40." The first number with the "W," which stands for winter indicates how well the oil flows at a colder air temperature, and the second number stands for how well the oil flows at a higher air temperature. The lower the W number, the less viscous your oil will become in colder temperatures.

Antifreeze and coolants

Although there's some water in your engine's cooling system, it can't run on water alone. Weak coolant, low coolant levels or a leak in the cooling system, such as in the radiator or a hose, can cause your radiator to overheat and cause the engine to stop running. Adding antifreeze and coolant raises both the boiling point and freezing point of the water. For example, a 50/50 mixture of antifreeze and water raises the temperature about 10 degrees Fahrenheit and lowers the freezing point to -35F, meaning your engine runs more efficiently in colder temperatures. Antifreeze is mostly available in gallon jugs.

Replacing antifreeze completely requires a flush and fill kit, which flushes all the existing coolant from the radiator so you can replace it with completely fresh water and antifreeze. Sometimes, radiators have leaks, and it's not always possible to replace the radiator. For those times, you can add a stop-leak product specifically designed for radiators and continue to drive your car until you can replace the radiator.

Transmission, brake and steering fluids

Transmission fluid serves as the lubricant for your vehicle's transmission. Like your engine, this component has numerous moving parts, so you need to replenish or drain and refill the fluid from time to time. This fluid also transmits power from your vehicle's engine to the transmission, causing it to move. Automatic transmission fluid (ATF) also serves as a coolant, keeping your transmission from overheating. Low power-steering fluid levels can cause your transmission to run hot, which is why it's important to top them off.

Brake fluid lubricates the moving parts in your vehicle's braking system. Also known as hydraulic fluid, brake fluid works at elevated temperatures and under high pressure like transmission fluid and motor oil do, making it possible for your vehicle to stop quickly when you step on the brake pedal. Low fluid levels make it harder to stop the vehicle and can cause your brakes to burn out.

Newer vehicles now have power steering as part of their drivetrains, and they require power steering fluid to operate the steering system. Power steering fluid is another hydraulic fluid that works with a pump that primes a piston mounted to your vehicle's rack. This makes it possible for you to turn the steering wheel to the right or left. Making sure that the power steering fluid is topped off prevents costly repairs later, such as having to replace the pump.

Other vehicle fluids

There are many other fluids that help keep your vehicle running properly.

• Windshield washer fluid This can clean your windshield of dirt, bugs and other debris better than water alone. Some also offer protection against winter weather and can remove ice, even at lower air temperatures.
• Air conditioner refrigerant If your air conditioner is blowing cool or warm rather than cold, it could be low on refrigerant. You can add your own using cans of refrigerant, many of which come with a hose that you can connect to your car, making refills easy.
• Greases and gear oil If you're particularly handy, you can lubricate your vehicle and its ball bearings using grease and gear oils. There are certain spots on your vehicle's chassis that need lubricating from time to time, and you can use lubricating grease that you pump into these areas.