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Emergency Scenarios: Leaking Fluid

Emergency Scenarios: Leaking Fluid

Fluids leaking from your vehicle can often cause a panic, but not all fluid leaks are cause for immediate concern. Identifying the substance can help you determine how major and urgent the repair is (if at all) and help you have a more intelligent conversation with your Sears Auto Center technician. Below, our experts have compiled some common liquids that can leak from your vehicle along with some tips to help you identify them*.

Fluid Leakage Safety

Motor Oil

This is the most common for several reasons.  First, it’s the fluid that’s most often changed, so residual spillage is often a cause.  Second, in most cars, there are more places for oil to leak out of.  If you see a large puddle, especially after a recent service, consult your service center immediately.

Sometimes, an oil leak will drip down on hot portions of the engine while it’s in use.  When this happens, you’ll have faint “burnt toast” smell during operation.  In some cases, you can see light blue-ish smoke emanating from under the hood.

If you are seeing any small, very slow oil drips from your car or truck, bring it in to your local Sears Auto Center for a free visual inspection. Even small leaks should be taken care of fairly quickly, as driving an engine with low oil levels can cause permanent damage.

Automatic Transmission Fluid

Automatic Transmission Fluid (ATF) is used in all cars that have automatic transmissions as a lubricant for the moving parts of your transmission as well as a coolant and viscous fluid that transmits power from the engine to the transmission.  It’s also used in some manual transmissions, transfer cases (for four- and all-wheel drive vehicles), and even in some power steering systems. ATF can be a number of different colors, but is traditionally red or pink.  As it ages, it becomes more brownish in appearance.  It has very little odor when it is new; although in some instances it can smell slightly metallic.  As it ages, it can begin to smell a tad like varnish. 

Puddles of fluid should be addressed right away.  Leaks are usually found in the front of the car in front-wheel-drive vehicles and near the middle of the car in rear-wheel-drive vehicles.  All-wheel drive vehicles could have leaks at either place.

Power Steering Fluid

Most vehicles use a special light hydraulic fluid for their power steering systems, generically referred to as “power steering fluid”.  It is clear to light-brown in color and smells faintly of rubbing alcohol.  It generally leaks from the front or the front-side of the vehicle.  Leaks should be addressed right away as a loss of power steering fluid can cause diminished steering control and result in an accident.

Coolant (Antifreeze)*

Coolant is usually green but can also be orange, yellow, red or somewhere in-between.  It’s most easily identified by its smell, which is very sweet. If your car is leaking antifreeze, something has malfunctioned and needs to be addressed.

Antifreeze (which also is used in your vehicle’s heating system) can also leak inside the car.  Most commonly, this leak is in the floorboard as it’s likely from a leaking heater core component, but sometimes it can blow out as a mist from the defroster. Typically, you’ll smell the antifreeze before you see it.  Any coolant leaks should be addressed right away.

*An important note about coolant: it is deadly if swallowed.  Not only to humans, but to pets and other animals as well.  Be sure to clean up any leaks or spills thoroughly and wash your hands well after any contact.

Differential Fluid

Rear-wheel and four-wheel drive vehicles use differential gears on the drive axle to shift the direction of rotation toward the wheels.  To lubricate those gears, these vehicles use very heavy oil that’s often gray or brown and has a pungent, distinctive odor.  Differential fluid leaks are often seen under the axle, but they can sometimes also leak out of the ends of the axle into the braking system and onto the tires.

Differentials don’t hold large amounts of fluid, so it’s critical that even a small leak should be addressed in short order.

Brake Fluid

Brake fluid is a hydraulic fluid, much like power steering fluid.  It’s light yellow to light brown in appearance and smells faintly of alcohol and metal. This is a critical fluid in your vehicle because without it, your brakes won’t properly stop your car.  And since the brake system runs from the firewall to each wheel, it can leak at any point under the car.  If you see any brake fluid leaking at all, do not operate the vehicle. If fluid has leaked out, then air has leaked in and can cause failure.

Fuel

The strong smell of gasoline is a give-away here.  If your vehicle is leaking fuel, it’s dangerous. Do not drive your car; have it towed to a repair shop as soon as possible. 

Water

Often times, especially on hot days, clear water can drip out from under the car.  Your air conditioning system creates condensation on the cooling lines and your vehicle is designed to dump this clean water onto the ground.

Other Fluids

Depending on your vehicle, there are other fluids or substances that can leak out of it. 

  • Bearing grease is always thick and tacky and can be found on the wheels.  This can indicate a serious bearing or seal problem and should be evaluated right away.
  • Some heated mirror systems use coolant that can leak out (and damage vehicle paint if not quickly attended to).
  • Windshield washer fluid is usually blue or purple and smells a little like ammonia.  This can leak from the reservoir in the front or from the back window if your vehicle is equipped with a rear window washer.
  • CV axle grease is brown, black or gray and is usually found slung on the inside of the wheel or the wheel well.  This is the result of a broken CV boot.  If you repair it immediately, you can often fix the boot instead of the axle and save yourself time and money.

Substance

Color

Smell

Location

Urgency

Safe to Drive?

Motor Oil

Black to brown

Bitter and/or smoky

Under the engine area

Depends on the amount.  One or two drops every few days is not serious.  If there is anything like a puddle, have the car towed to your repair shop.

Not always.

Transmission Fluid

Reddish, pink to brown

Very little odor if in good condition.  Varnished smell if older.

Under the transmission (front in front-wheel-drive cars, in the middle toward the front in rear-wheel-drive cars, and in either place in all-wheel-drive cars)

Depends on the amount.  Could be serious if there is a puddle.

Not always.

Power Steering Fluid

Clear to light brown

Slight alcohol smell

Near the engine area

Fix ASAP.  Losing power steering fluid can cause diminished steering control and result in an accident.

No.

Coolant (Antifreeze)

Green. yellow or orange/red

Very sweet

Anywhere under the engine area or in the floorboard (if heater core is leaking)

Antifreeze should NEVER leak out.  If it is, the cooling system has been breached or the thermostat is malfunctioning and the heat is forcing fluid to boil out.  Repair immediately and never run an overheating engine.

No.

Differential Fluid (also often used in manual transmissions)

Gray or brown

Pungent and very unpleasant

Under the rear axle in rear-wheel-drive vehicles and under rear or front axle in four- or all-wheel-drive vehicles.  Under the transmission in some vehicles with manual transmissions.

Differentials generally do not have large capacities; there isn’t a lot to leak out.  Repair as soon as possible.

Yes.

Brake Fluid

Yellowish to light brown

Slight alcohol/metal

Near each wheel, under the firewall or almost anywhere under the vehicle where the brake lines flow.

ALL brake line leaks are serious.  Have your vehicle towed to the nearest service center.

No.

Fuel

Clear to light yellow

You know what fuel smells like

Anywhere under the vehicle

Extremely dangerous.  Do not drive the vehicle and have it towed to a service center immediately.

No.

Water

Clear

Odorless

Dripping under vehicle—especially on hot days when A/C has been on

Not serious.  Condensation from your air conditioning is normal

Yes.

 

Regardless of what is leaking out of your car, our expert technicians can take a look and give you a diagnosis for free with our Performance Snapshot Evaluation

*If you park your car on a black driveway or are having trouble identifying a liquid by color, try placing a flattened cardboard box under your car overnight.

 

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