How Much Do You Know About Your Car's Fluids and Lubricants?

Maria Trimarchi

Which fluid is used to clean your car's windows, while you drive?

We take it for granted now, but when the first windshield washer unit was sold in 1936, it was aftermarket. Today, brightly colored fluid containing methanol and sometimes other alcohols such as ethylene glycol are also added, is used to clean windshields, as well as rear windows and, in some cars, headlights.

Which fluid keeps your car's front tires turning left and right?

It lubricates your car's power steering pump unit -- and that's important because that's part of the car's power steering system. Ultimately, by keeping the power steering pump unit running smoothly, power steering fluid is keeping your car's front tires moving.

What petroleum-based liquid is used to power a car's internal combustion engine?

Known as gasoline among North Americans (in contrast, it's called petrol in the UK), it's been used to fuel our cars since the first internal combustion engine-powered vehicle rolled down the road.

What is used to lubricate your car's engine?

Engines have a lot of moving parts, and the friction caused by that movement creates heat. Engine oil is what's used to keep all those pieces lubricated, and to make sure those internal parts don't get too hot.

While older model cars use conventional engine oil to keep things moving, what is used for engine lubricant in modern cars?

This type of engine oil is just as it sounds -- it's an engine lubricant, just like conventional oil, except unlike conventional oil it's engineered from artificial ingredients. Not every car will benefit from synthetic, but it's known to last longer than conventional -- and you can always switch back if synthetic isn't working out.

Which is not a way WD-40 can be used on your car?

Dissolve rust? Check. Dissolve grease? Check. WD-40 is just one of those things that's useful to have around because it can do so many things -- more than 2,000, according to the company that makes it. But as a fuel? Just say no.

If your car has an automatic transmission and you notice it hesitates when shifting gears, what's the first fluid you should check?

If your car has an automatic transmission and seems to be hesitating when shifting gears, the first thing to check is the transmission fluid. To do so: While your car is running and safely in Park with the parking brake on, pull out the dipstick from the transmission. Check the color and clarity of the fluid (it should be pink-tinged and nearly clear) -- if it's dark or smells bad, have it changed. Also, check the level of the fluid -- if it's low, top it off.

Although engines powered by it were used in the 1930s, it wasn't until the 1960s when what fuel became more mainstream?

Car companies Citroën, Mercedes-Benz and Hanomag were all featuring diesel engines in certain cars as far back as the 1930s. But it wasn't until the post-WWII cars, including those from Volkswagen and Peugeot, rolled off the line that the engine gained more attention for passenger cars.

Classic cars may benefit from which gasoline additive?

When it comes to caring for a classic car, specifically any car without hardened valve seats, you might need to consider a bottled lead replacement additive. Due to concerns about its toxicity, leaded gas began being phased out in the U.S. in the mid-1970s, and was finally gone 1996. Cars that once ran on leaded gas may benefit from lead replacement additive (specifically, tetraethyl lead, or TEL) to help boost octane and reduce knocking.

What can be used to lubricate materials without liquid?

Graphite dry lubricant can be used on metal, plastic, rubber and wood surfaces to reduce friction and pressure on them -- without liquid.

What type of product is used to keep moisture out of your car's electrical connections?

Dielectric grease is best used on electrical connections where you don't want moisture to penetrate. It's a silicone grease that doesn't conduct electricity, and is commonly used to grease your car's spark plugs.

What fluid can provide a temporary fix if you feel your car's automatic transmission "shudder" when you're driving between 40-60 mph?

If a car's transmission "shudders" for a few seconds at speeds between 40 mph and 60 mph, the problem is often a slipping torque converter clutch. While it's a temporary solution, a transmission modifier added directly to the transmission fluid can stop the shudder. Until the 1970s, this was whale oil, but today these are non-solvent transmission additives containing a blend of friction modifiers and other petroleum-based additives.

5W- engine oil is typically recommended for what kind of weather?

The first number in how oil is classified refers to its viscosity at certain temperatures. The lower the number, such as "5" in this instance, the thicker the oil will be at lower temperatures. At the low-temperature end, oil has to be resistant to thickening so that it flows more easily to all the moving parts in your engine. There's even a 0W, for when it's really really cold.

Which grease is a type of anti-seize grease?

Copper grease is a thread lubricant that's used to prevent corrosion and seizing. It can withstand high temperatures, and is used on nuts and bolts, exhaust brackets, and to help prevent disc brake squeal.

Which fluid is used to keep your car's engine from getting too hot or too cold?

Coolant, or antifreeze, is what protects the inside of your engine from corrosion, as well as from boiling over or freezing. Most types use ethylene glycol, which gives it its sweet, but dangerous, smell.

What type of lubricant is used in a pressurized system, such as your car's air conditioning system?

It's vacuum grease that's made to seal and lubricate joints among other parts and pieces of vacuum systems and pressurized systems such as your car's air conditioning.

Which fluid lubricates the ring and pinion gears that transfer power from the driveshaft to the wheel axles?

Your car's differential is a gearbox that sits between the drive wheels -- and if you drive a 4WD vehicle, there is one in the front and one in the rear. The purpose? It's what makes your car's wheels spin -- the differential transfers the power your engine makes to the axles, which is what turns the wheels, and allows the car's wheels to spin at different speeds around corners. The lubricating fluid inside the differential reduces friction and keeps the gearbox running smoothly.

Is radiator coolant the same thing as engine coolant?

Yes, radiator coolant is the same thing as engine coolant, and also the same thing as antifreeze. Its radiator is what's used to cool your car's internal combustion engine. It works, basically, like this: The force of the car's water pump pushes coolant through the car's engine block where the coolant heats up, before it then circulates through the radiator to cool down -- and then repeats.

Which hydraulic fluid is used in your car's anti-lock brake system?

Brake fluid, which is a type of hydraulic fluid, comes in two main types: glycol-based, which is typically used for anti-lock brake systems (ABS), and silicone-based, which is used in vehicles without ABS. Brake fluid, which you'll find in your car's brake lines, is what keeps the components of the braking system moving.

What fluid should be checked if your 4WD vehicle jumps in and out of 4WD?

In 4WD and AWD vehicles, the transfer case is what sends power from the engine to the car's front and rear axles -- it shifts the power from one axle to another, depending on what your traction needs are, which means a lot of wear and tear on the gears. That's where transfer case fluid comes in; it reduces friction and heat, and keeps those gears smooth.

What can a penetrating fluid do?

Penetrating lubricant is low-viscosity oil used to loosen and lubricate in very narrow spaces, such as the threads of seized or rusted nuts and bolts. It's also able to remove adhesive materials such as bumper stickers from your bumper or gum from your carpet.

Engine oil is separated into different viscosity grades. In 10W-40, what does the "40" mean?

The second number on your oil, in this case the "40" in 10W-40, gives you information about the oil once the engine's running and the oil is heated up -- basically, the lower that second number is, the thinner the oil will be at 210° F (100° C), which is the normal temperature of your car's engine when it's operating. So a 10W-40 oil will be thicker when the oil heats up than if the oil is rated at a lower number, like 10W-30.

When working on your car, what would you use a grease nipple for?

A grease nipple, also called a grease fitting, is a metal fitting that you or your mechanic would reach for when you need to use your grease gun to feed a lubricating grease into a metal bearing, for instance.

In an emergency, what can you use if your car's overheating?

Your car's overheating and you don't have coolant? In a pinch, there's water -- long term it's not good for the inside of your engine block, though, because it's corrosive, so keep it to emergencies only.

There's a lot of wear and tear on a car's air conditioning system. What helps lessen the friction?

Think about how often it's turning on and off, again and again. There's a lot of wear and tear on your car's air conditioning system, but air compressor oil can keep the compressor in the A/C system running rust-free and smooth.

Which sticky paste is a key ingredient when mounting new wheels?

Reach for tire and tube mounting compound when you're mounting rubber tires -- or, as you might suspect, tubes. It's what lubricates the bushing, rubber-mounted spring shackles, and fan belts, and seals tire beads -- and it also has rust inhibiting qualities.

What type of engine oil does a two-stroke engine require?

Unlike the four-stroke engine in most cars, two-stroke engines are lightweight and mechanically simpler, with a higher power-to-weight ratio -- and often these small engines use an oil-fuel mixture instead of conventional motor oil. In these cars, it's two-cycle, or 2T, a "petroil" that's used to lubricate.

What waterproof, temperature-resistant grease is used to reduce metal-to-metal friction?

It's non-corrosive and waterproof, and it's engineered to work in any metal to metal situation where you think water penetration could be trouble.

What element is added to white lithium grease to help you see it?

The chemical element -- and essential mineral -- zinc is added to white lithium grease. It's not for performance; rather, it's so you can see it.

Coolant used in a diesel engine isn't the same as that used in a gasoline engine. Why?

They're both internal combustion engines, but they don't work quite the same way -- and that means the coolant used for a diesel engine is a little different than that used with a gasoline engine. Specifically it has to do with something called cavitation. Because cavitation, which is erosion of the cylinder walls, can happen in a diesel engine, diesel-friendly coolant is formulated to prevent that.

Which type of grease is formulated to handle the high temperatures of disc and drum brakes?

High-temperature wheel bearing and chassis grease is a go-to lubricant for both disc and drum wheel bearing applications. In addition to being able to handle the hostile environment, this grease is also water-resistant, anti-wear, and also contains corrosion inhibiting ingredients.

If you plan to store your car for a month while you travel, what will keep its gasoline from turning bad, gumming up the works while you leave it in the garage?

If you're going to store your car (or any gasoline equipment, for that matter) for a length of time between 30 days and a year, a fuel stabilizer can help keep the gas in your tank from deteriorating. Plus, it can be used in all gasoline types.

What lubricant is engineered specifically for your car's transmission, transfer case and differential?

Gear grease and gear oil is used in a car's transmission, transfer case and differential to reduce friction between the teeth of the gears, as well as to reduce the temperature caused by all that friction. Without proper lubrication, the teeth can wear prematurely -- and wear out prematurely, too.

What pour-in additive will help keep the combustion chamber of your car's engine free from performance-reducing build-up?

Gasoline, in particular the use of ethanol as an octane-boosting ingredient in some types of gasoline, can cause build-up in your car's fuel injectors, on its intake valves as well as in the combustion chamber in the engine. Over time, the build-up can reduce your car's fuel economy, and you may find it also hurts performance. Some argue it's not necessary, while others swear by a pour-in fuel system cleaner to remove those byproducts.

What fluid improves the performance of your car's air filter?

When it comes to your car's air filter, especially if it's a high-performance filter, air filter oil can help it perform even better. Applied to the filter and allowed to dry, the addition of air filter oil means the filter is not only better at filtering out debris and other contaminants, it's also gotten a boost in water-resistance.

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About This Quiz

Get your motor runnin', head out on the highway -- lookin' for adventure, and whatever comes your way ... but you can't be an Easy Rider if you don't know the basics of car maintenance. See how much you know about keeping your car tip-top.

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