We can look back through history over a long list of dynamic duos that made for a good match, both in fiction and in real life. We remember famous names like Abbott and Costello, Oscar and Felix, or Bert and Ernie. Or maybe Batman and Robin, or Frodo and Sam, or Calvin and Hobbes. The list could go on for a good long time with characters that just fit together well.
But there are some characters, like Bonnie Parker and Clyde Barrow, whose chemistry made for a dangerous cocktail when mixed together. The same might be said (although to a far less dramatic degree) when you mix up the fluids in your car.
For your vehicle to work properly, there are several fluids to aid in cleaning, cooling, lubrication, and hydraulics. Each fluid is carefully developed for its purpose: engine cooling and lubrication, transmission of power, braking, and more. And each fluid is kept separate in its respective system.
From time to time, the fluids in your car need to be replaced or replenished as part of routine vehicle maintenance. For instance, it might be necessary to “top off” the oil in your engine if you find that the level is a bit low in between oil changes. Or you might need to add some solvent to the windshield washer reservoir. In each case where you might add fluid, it is essential that you add the correct fluid. Installing something else could cause damage and render the system ineffective or inoperative.
So, how do you avoid a Bonnie and Clyde mixup? Well, here are some mismatches to steer clear of…
Motor oil is often referred to as the lifeblood of an engine. All of the metal components inside, moving at thousands of revolutions per minute, would die a quick and painful death if not for the thin coating of lubrication between them that motor oil provides. For proper lubrication to take place in your engine, the right oil needs to be used.
Vehicle manufacturers design each engine to run with a specific type and viscosity, or grade, of oil. The viscosity (grade) is basically a measure of the thickness of the oil and is indicated by a code: 5W-30, 5W-20, 0W-20, and so forth. The higher the number, the thicker the oil; the lower the number, the thinner. The type of oil refers to whether it is a synthetic oil product made artificially in a lab, or a conventional oil. Where one engine might call for a viscosity of 5W-30, another might need 0W-20; one cannot be substituted for the other. And while some engines come from the factory with synthetic oil installed, others rely on regular old conventional oil.
So, where is the concern when it comes to adding engine oil?
Well, first of all, no other lubricant will serve in your engine; no cooking oil or other such product will do. Feel free to switch between brands of oil (such as replacing the original oil with Mobil 1), just make sure to use a quality motor oil.
And make sure it is the same viscosity. Your vehicle owner’s manual will advise as to what grade is needed in your engine. If the oil you add is too high in viscosity, it will not be able to squeeze into the tight spaces between engine components. If, on the other hand, it is too low in viscosity, it will fail to form a consistent lubricating film and invite metal to metal contact.
Many manufacturers are moving to synthetic motor oils as original equipment, especially for those engines that require the lowest viscosities (i.e. 0W-20 or 0W-16). Synthetics offer several advantages in addition to low potential viscosity. They are capable of lasting longer between each oil change, what is known as an extended oil change interval. Because they are created artificially in a lab, synthetic oils are more uniform and hold up better than their conventional counterparts. They also include advanced additives to clean and protect the inside of your engine.
If your engine comes with synthetic oil, replace it with synthetic oil. On the other hand, if it has conventional oil, you are free to use either one. It is perfectly fine to switch from conventional oil to synthetic oil (and back again) as long as the manufacturer does not call for synthetic. And there is no danger in mixing the two; they are compatible. Just remember, if you add conventional oil to synthetic, you reduce the effectiveness of the synthetic. So don’t do that if your engine requires synthetic oil.
Finally, if you are considering the use of aftermarket oil additives to enhance the performance of your motor oil, you might want to think again. Some vehicle manufacturers advise against it, and in some cases, the use of oil additives can void your new car warranty. Besides, modern motor oils have all of the additives they need right from the bottle, especially if the product is synthetic.
Power Steering Fluid
Motor oil is a big one given the importance of your engine. But it is not the only fluid that is subject to improper refilling. Power steering fluid is a hydraulic fluid that allows for power assist when you turn the steering wheel. Some vehicles feature an electric power assist that relies on an electric motor attached to the steering shaft, but most power steering systems are hydraulic and need power steering fluid.
If you are topping off the fluid, you might find that your owner’s manual (or the cap to the reservoir) suggests that you can substitute Automatic Transmission Fluid (ATF) in place of the power steering fluid. That is because the two are very similar in composition. For decades, auto owners have been adding ATF to their power steering fluid reservoirs.
But that is not always the case. Some systems rely on a mineral oil-based fluid that is not compatible with ATF. If you make the substitution when that is the case, you could cause damage to the system, including deterioration of the seals and leakage.
Make sure that ATF is recommended as a replacement for your power steering fluid before using it.
Automatic Transmission Fluid
Although ATF and power steering fluid are similar and (in some instances) compatible for use in your power steering system, that is not the same as saying they are completely interchangeable. They only have similar makeup and properties as a hydraulic fluid, not for all of the other functions necessary in your automatic transmission. There, the ATF must also function as a lubricant, a coolant, and a cleaner. Power steering fluid does not do those things and should never be used in your transmission.
As a side note, your ATF should never be overfilled. Overfilling your transmission can lead to excessive pressure and the introduction of air into the fluid, causing the fluid to lose its ability to lubricate and your transmission to overheat and break down. For this reason, manufacturers are increasingly moving toward transmissions that are not user-serviceable.
Of course, your engine is essential to get your car moving. So is your transmission. And your power steering allows you to move in the right direction. But none of that matters very much if you are not able to stop when you get there.
Your brakes are the most important safety feature on your vehicle. The brake system is made up of a hydraulic pump (the master cylinder) that applies force against brake fluid in a matrix of tubes that lead to each wheel when you press on the brake pedal. That brake fluid serves to transfer the pressure from the pump to the brake pads that slow and stop your wheels and your car. Therefore, the brake fluid must be in good condition, clean and free from air and moisture.
Adding anything but fresh brake fluid (that is not out of date) to the brake reservoir will diminish the effectiveness of your brake system. Some drivers mistakenly add ATF to the brake system like they might the power steering. This is a definite no-no! ATF will eat away at the seals of the master cylinder and other system components, cause leaks, and destroy your brake system.
Also known as “antifreeze” for its ability to withstand cold temperatures, engine coolant serves to regulate the operating temperature of your engine. The combustion process produces a significant amount of heat – too much, in fact. Your engine has an optimum operating temperature at which it works most efficiently, usually somewhere around 200 degrees Fahrenheit. When the temperature climbs above the mark, coolant is circulated through the engine block and takes heat with it when it leaves, losing that heat to the environment through the radiator. When the engine cools down, the thermostat (a device that senses and regulates temperature) closes and keeps the coolant from circulating.
The basic ingredients that make up engine coolant are ethylene or propylene glycol and water. It also includes additives to help prevent corrosion of engine components. The balance of coolant to water is somewhere around 50/50 and needs to be maintained there.
Over time, some of the coolants in your engine will evaporate, therefore it is necessary to top it off by adding coolant to the overflow tank or reservoir, or possibly to the radiator itself. When you do, make sure to use either a pre-mixed product or mix a concentrate with an equal amount of water. If you add only water, your engine might overheat, and the water could freeze in the cold and destroy your engine. Too high a concentration of coolant can also lead to overheating. (Note: never add engine coolant to a hot engine!)
Windshield Washer Solvent
Most bottles of solvent aimed at cleaning your windshield have printed somewhere on the label the word “antifreeze”. That is because washer solvent must be able to withstand freezing in the winter. That is not because it is a suitable replacement for engine coolant. Do not use washer solvent in your radiator like the fifteen-year-old version of a certain automotive writer did decades ago.
But do not use straight water either. Washer solvent contains chemicals to remove contaminants and prevent streaks on the glass; water does not. And water will freeze when it gets cold. Also, avoid household products as they can also cause streaks, but more importantly, they can damage the paint on your car and introduce noxious vapors into the passenger compartment.
How nice it would be if every partnership was a benevolent one. But we know that is not always the case. And it would be oh so simple if every system on a vehicle used the same type of fluid. That way there would be no cause for concern, nothing to mix up. But the world just doesn’t work that way – neither does your car. Make sure to avoid creating a cocktail of incompatible chemicals when adding fluids to your car.
Columbia Auto Care & Car Wash | Author: Mike Ales | Copyright
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