AUTONET TV

The McLearen Shell Guide to Servicing Your Differential

Differential? What's that? And what's it for? I've been told by my service advisor that I need to get it serviced, but is that on the level?

Do these questions sound familiar? They're not uncommon for Herndon drivers. A lot of us in Herndon don't know what a differential is or what it's for. Every vehicle has a differential, and, yes, it does need to be serviced. In fact, it's more important to the operation of your vehicle than the air conditioner or windshield wipers.

A differential allows your vehicle tires to move at different speeds. This happens more than you think. The best example is when a vehicle is turning. The inside wheel travels a much shorter distance than the outside wheel during a turn. This means the outside wheel has to move faster than the inside wheel. Without a differential, your tires would hop and skip while turning. They would also lose traction in sand or snow.

The location of your differential depends on what kind of vehicle you drive. On a rear-wheel drive vehicle, the differential is located in the back. For a front-wheel drive vehicle, it is located on the front, but it is usually called a transaxle. Four-wheel drive vehicles have three differentials: one on the front, one in the back and one in the middle. This center differential compensates for differences in speed between the front and rear wheels.

Your differential contains strong gears that need to be protected from dirt, debris, water and other contaminants. A differential is sometimes referred to as a “gear box.” The work of these gears is to transfer power from the vehicle drive train to the wheels.

Your differential needs fluid to lubricate and cool the gears. This fluid, even though enclosed in the “gear box,” can get dirty because the gears grind down over time, releasing tiny bits of themselves into the fluid. Also, the additives in the differential fluid break down and need to be replaced. That's why preventive maintenance for your vehicle needs to include servicing the differential.

Your owner's manual can give you recommendations on how often to service your differential. But you should also consult with your friendly and knowledgeable McLearen Shell professional. McLearen Shell can give you some good auto advice on whether your vehicle needs to be serviced more frequently. For example, if you drive in hot or cold VA weather conditions, your differential will need to have its fluid changed more often.

Severe conditions will also affect your vehicle care routine and your differential. Check your owner's manual for a definition of “severe service” conditions that affect your vehicle. Examples may include driving with frequent stops and starts, a lot of short trips around Herndon, hot or cold VA weather conditions and towing.

Off-roading is particularly hard on a vehicle's differential. If you are an off-roader, especially if you cross VA streams or waterways, it is important that you service your differential more frequently than the recommendations suggest.

Properly servicing your differential will extend its life and keep you out of Herndon auto repair shops. A smooth ride is the result of proper preparation and smart choices.

 McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
www.mclearenshell.com

PCV Valve: What Is It?

Most Herndon drivers know something about preventive maintenance on a vehicle. We know we should routinely replace the oil and wiper blades and other fluids. But have you heard of a PCV valve ? This little car part needs to be replaced regularly or it can cause some serious problems in your vehicle engine.

PCV stands for Positive Crankcase Ventilation. The crankcase holds your motor oil and is located at the bottom of your engine.

When fuel is burned in your engine, it produces waste gases that are mostly vented out through your exhaust system. But some of these gases push their way past the pistons and into the crankcase. There, these gases can mix with motor oil to produce oil sludge, which can damage vehicle engine parts through corrosion and by clogging engine passages. Herndon vehicle owners should be advised that if the engine is running at high speeds, these gases can also cause pressure inside the crankcase to build up. This pressure, in turn, can blow gaskets and damage seals, leading to oil leaks.

The waste gases that leave the engine are comprised of about 70% unburned fuel. They used to be vented off the crankcase into the atmosphere. But starting in 1964, laws mandated that these gases be recaptured. Manufacturers began installing PCV systems, which recycled the gases into the air intake system where they could be mixed with fuel and sent to the engine to be burned.

The PCV valve is a one-way valve attached to the crankcase. Waste gases exit the crankcase through the valve but cannot enter.

Over time, the waste gases leave deposits on the PCV valve that can gum it up. So it needs to be replaced occasionally. This is an inexpensive part of preventive maintenance that is often overlooked, but which can have very expensive consequences. It's good auto advice to keep this little valve clean and working well.

In order to maintain efficient circulation, the PCV system also has a breather tube that allows clean air to enter the crankcase. This air is usually filtered through the engine air filter. But some vehicles have a separate air filter for the breather tube called the breather element. If this is the case with your vehicle, proper maintenance of the PCV will include replacing this element. To find out whether your vehicle has this type of PCV system, check your owner's manual or ask your service advisor at McLearen Shell.

The PCV system reduces harmful vehicle emissions. The maintenance it requires is simple and inexpensive at McLearen Shell. A fouled or damaged PCV system can lead to serious engine damage for Herndon drivers.

Let's all learn to practice good car care. It's good for our wallets, and it's good for our VA environment.

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
www.mclearenshell.com

Deep Clean Your Fuel System at McLearen Shell

Having trouble with your fuel system? Bring your vehicle into McLearen Shell for a check up.

In today's McLearen Shell auto post, we're talking about fuel system cleaning. The first thing to know is how important it is to have a clean fuel system. Herndon residents need fuel to go, and the cleaner the fuel system, the more efficiently the fuel will burn. That means more power and better mileage .

A clean fuel system saves money for Herndon drivers at VA gas stations. We guess you could say it all starts and ends at the pump. One of the most important things Herndon residents can do to keep their vehicle fuel system clean is to buy good quality gas. Major brands have detergents that keep gum and varnish from rapidly building up in the fuel system.

So buying cheaper gas in VA can actually be more expensive for Herndon drivers in the long run. Now, most cars on VA roads are more than five or six years old. That means they've had time for some dirt and rust to start accumulating in the fuel tank. This junk needs to be filtered out of the fuel before it hits your vehicle engine. That's the fuel filter's job.

When the fuel filter is clogged, the dirty fuel will bypass the filter and go on up to the engine where it can clog fuel injectors and get into the cylinders. So Herndon residents should have their fuel filter changed when recommended. Check your owner's manual or ask your friendly and knowledgeable McLearen Shell service advisor if your fuel filter is due for replacement.

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
www.mclearenshell.com

Which Item Is Most Stolen from Vehicles in Herndon?

Which item is most often stolen from vehicles in Herndon?

Is it:

1. Stereo
2. Wheels
3. Air Bag
4. DVD System

Well, if you said stereo – you used to be right. But airbags have now surpassed stereos as the biggest target for theft in VA – approximately 50,000 a year are stolen across the country. New airbags cost about $1,000, but go for $50 to $200 on the black market in VA.

Stolen airbags are making their way back into cars that have been in an accident. Of course, the danger to the consumer of having a stolen airbag installed is that you can never be sure what may have previously affected them and if they will work right when you need them.

Contact us at McLearen Shell for more information about where to get your airbags checked or replaced.
Find us at 3043 Centreville Road, Herndon, VA 20171
You can reach us by phone at: (703) 318-7744

There are reports that 1 in 25 airbag replacements are stolen or salvaged airbags – or no airbag is installed at all.

That is definitely one car part you don't want to take a chance with, so McLearen Shell recommends following these guidelines:

• Use a reputable collision repair center that employs ASE certified mechanics (we can offer recommendations at McLearen Shell).

• Inspect the invoice to ensure that the repair shop purchased the airbag from a manufacturer, dealer or recycler. If you can inspect the airbag prior to installation, it should be packaged in a sealed container from the manufacturer.

• You will see the SRS light (Supplemental Restraint System) when you first start your vehicle up. This tells you that the airbag system is activated. If you do not see the SRS light, there is likely a problem with the airbag system.

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
www.mclearenshell.com