Differential ServiceOctober 23, 2012

Here at AutoNetTV, we have viewers, like you, from all across the country who write to us with questions or feedback. One common question we’re asked is: What is a differential and what does it do? You may have been told your differential needs service, or seen it as an option up on the service menu. Differential service covers a lot of things, so let’s first talk about what a differential does.

As you drive through a turn, your outside wheels and inside wheels turn at different speeds. Kind of like the cars going around a race track – the ones driving in the outside lanes have a greater distance to travel than the cars in the inside lanes. The differential is what allows the outside and inside drive wheels to rotate at slightly different speeds so that the tires don’t hop or skip while taking corners, or lose traction in dirt or snow. Differentials have gears in them that transfer the power from the drive train to your wheels – which is why they’re often referred to as gear boxes. The gears need to be very strong to do this work, and they need to be properly protected so that they’ll last.

All vehicles have some form of differential. If you have a front-wheel drive car, your differential is often called a transaxle and is located in the front. If you have rear-wheel drive, the differential is in the back of the car. If you have a four-wheel drive vehicle, you will have a differential in the front and the back – and in the middle as well. The center differential adjusts for differences in speed between the front and rear wheels.

Differential fluid lubricates and cools the gears. Over time, the fluid can get dirty from bits of the gears grinding off. The additives that keep the fluid clean and protect the differential break down over time. So your vehicle manufacturer has scheduled intervals for you to have your differential fluid changed.

Differentials are hard working mechanisms, and, along with the gears in a manual transmission, need to be serviced regularly with high-quality, replacement fluid. Your Rowlett automotive service advisor can give you more information as to when your next differential service is recommended. You can also ask if they have a record of when the service was last completed.

As with most service intervals, if you are driving under more severe conditions, you will want to service your differential more frequently. “Severe service” conditions are defined in most owners’ manuals, and include: frequent starts and stops, short trips, cold weather, hot weather and towing. All these conditions add to the stress of the vehicle and its parts. Also, off-roading in TX can be especially hard on differentials, especially if you cross streams. Proper service will extend the life of your gears and keep them running more smoothly. If you have never had your differential checked, visit contact-us for more information.

Exhaust ServiceOctober 23, 2012

Whenever we talk about exhaust service, most people normally think about exhaust pipes and mufflers. Well, actually, exhaust service is a lot more comprehensive these days. For example, catalytic converters were mandated in 1976 and on-board emission control computers in 1990. Governmental emissions requirements have forced manufacturers to come up with much more sophisticated ways to comply with environmental regulations.

Exhaust service has really become exhaust and emissions service. High-tech computer controlled emissions devices are now a big part of exhaust service. Because it is so sophisticated, your vehicle manufacturer recommends you have your emission system checked out by a qualified Rowlett exhaust technician regularly to make sure everything is working right – usually every 6 months or 10,000 miles/16,000 kilometers.

If your Check Engine light comes on, especially if it’s flashing, get your car looked at right away. Technicians at Lewis Complete Auto Repair handle emission problems everyday. You might have exhaust or emissions trouble if your car is difficult to start, runs rough, is noisy or smoking. Call Lewis Complete Auto Repair at 972.475.4800 to schedule an appointment if you experience these problems.

Let’s review the exhaust system. We will start from the top and start with the exhaust manifold. That is the part that attaches to the engine and collects the exhaust from the cylinders and directs it into the exhaust pipe. Exhaust gaskets help seal the connection with the manifold and various other joints along the way. If the manifold is cracked or loose, or a gasket is leaking, dangerous gases could escape into the passenger compartment, where you ride. Carbon monoxide can be deadly, so it is important that your exhaust system doesn’t leak. The exhaust pipes connect the various components. They can rust or be damaged by a rock, so they need to be inspected periodically.

Next is the catalytic converter. This part looks like a muffler. It changes chemicals that are dangerous to your health and the environment into harmless carbon dioxide and water. It doesn’t require any maintenance itself. But eventually they wear out. You will find this out when your car fails an emissions inspection.

Now the muffler. Its main job is to quiet engine noises. Mufflers work by either absorbing or baffling sound. And you can actually customize your car’s sound with different mufflers – anything from whisper quiet to bad-boy rumbley. Rusted or road-damaged mufflers can leak and need to be replaced right away.

The exhaust system is attached to the car by a series of hangers and clamps. These fasteners hold the system in place. When hangers come loose or break, hot exhaust components can touch and melt wires, hoses and lines.

Finally, we end at the tailpipe. This is the final outlet for the exhaust. These can be plain-Jane or pretty flashy. Also, the oxygen sensors monitor the oxygen content of the exhaust so the engine control computer can adjust the fuel-to-air mix to keep the car running right.

Exhaust and emissions service covers plain old pipes and high-tech computers. It impacts everything from life and death safety due to exhaust leaks, to fine-tuning the sound of your ride.

Lewis Complete Auto Repair Radiator ServiceOctober 23, 2012

The coolant system is a vital part of your vehicle. It is also the second most common cause for vehicle failures. Even though coolant system failure is fairly common, it is easy to prevent.

Lewis Complete Auto Repair
5110 Grisham Dr.
Rowlett, TX 75088
972.475.4800

The most recognizable part of the coolant system is the radiator. It is connected to the engine with hoses and is filled with coolant. The coolant draws heat off the engine and then goes into the radiator. Air passes through cooling fins to reduce the temperature of the coolant and then it’s back to the engine again.

There are several ways for the cooling system to fail. Most common is with the coolant itself. Coolant is a mixture of water and antifreeze. The proper mixture keeps the coolant from either boiling away or freezing. Both of which can result in massive engine damage.

Another very important coolant issue that is often overlooked is the age of the coolant itself. Antifreeze has additives that protect the coolant system from corrosion. As these additives are depleted over time, they can’t protect the radiator and other parts from rust, scaling and corrosion. Old coolant may still keep your engine cool, but it won’t protect it from corrosion.

If you see a warning message to check the coolant or if the temperature gauge is in the hot zone your cooling system needs to be checked. It’s OK to add water or antifreeze yourself. But you need to be cautious. Remember four things.

  • First, you never want to open the radiator pressure cap. You could be severely burned.
  • Second, try to get to your Rowlett service center at Lewis Complete Auto Repair immediately if your coolant is low. If that is not possible, follow the directions in your owners manual – it will direct you to only make additions to the coolant overflow bottle.
  • Third, remember that you need a proper mixture of water and antifreeze. If you make an emergency addition to your cooling system, follow-up with your Lewis Complete Auto Repair service center where we can make necessary corrections.
  • Fourth, not all cars use the same type of antifreeze. You need to check your owners manual to make sure you use the right kind. Mixing antifreeze types or using the wrong kind of antifreeze may void the manufacturers warranty on your cooling system. Again, another reason to rely on your Lewis Complete Auto Repair service center in Rowlett to do things right.

Remember, your Rowlett service center has the equipment to change your coolant quickly and inexpensively.

Power Steering Service Near RowlettOctober 23, 2012

For most of us living in the Rowlett area, it is hard to remember life without power steering – cranking those great big steering wheels? It was a pretty good workout. Now power steering is standard. The heart of any power steering system is its pump. The pump pressurizes the power steering fluid that provides assist for steering. Most pumps are driven by a belt that is run by the engine – a few are electrically powered. A high-pressure hose passes fluid from the pump to the steering gear. A low pressure hose returns the fluid back to the pump.

These hoses can develop leaks, so it is a good idea to inspect them at every oil change. Low fluid can damage the power steering pump. That is why fluid level is on the checklist for a full-service oil change. The fluid needs to be compatible with the hoses and seals, so check your owners’ manual for the right type – or just ask your service technician at Lewis Complete Auto Repair.

The fluid cleans, cools and lubricates the power steering system. It breaks down as the years go by and collects unwanted moisture, so it needs to be replaced from time to time. Many manufacturers specify power steering service intervals. Unfortunately, this important service is sometimes left off the maintenance schedule for many of us in Rowlett. So, when in doubt, every 25,000 miles/40,000 km or two years is a good fallback. Your Lewis Complete Auto Repair service center in Rowlett will use a detergent to clean the system, flush out the old fluid and replace it with the good stuff.

Here are some warning signs of trouble with your power steering: It’s harder to turn the wheel, there’s erratic power assist, you hear loud whining coming from the pump (which may be difficult to hear over the loud whining coming from the backseat), you have to top-off the fluid frequently, or you hear squealing belts. Remember to never hold the steering wheel to the far right or left for more than a few seconds at a time. That will wear out your power steering pump real fast.

Other steering components can be bent or damaged from wear or hard knocks. Ball-joint, idler-arm, steering-gear, steering-knuckle and tie rod to name a few. Warning signs here are steering play, wandering, uneven tire wear, and off-center steering wheel. An annual alignment check at Lewis Complete Auto Repair will reveal bent or damaged steering components.

Most SUV’s, pick-ups and rear-wheel-drive cars need regular front-wheel-bearing service.

The bearings should be cleaned and inspected. If they are excessively worn, they need to be replaced. The bearings are then repacked in clean grease. It’s also recommend the wheel-seal be replaced when the bearings are serviced. Like everything else, check your owners’ manual maintenance schedule. It’s usually required around every two years or 40,000 miles/64,000 km. If you drive through water in the Rowlett area, the bearings will need service more often.

Lewis Complete Auto Repair
5110 Grisham Dr.
Rowlett, TX 75088
972.475.4800

PCV Valve ReplacementOctober 23, 2012

The energy from exploding fuel is what powers your engine. But some of the vapors from the explosions escape into the lower part of the engine, called the crankcase. The crankcase is where your engine oil hangs out. These gases are about 70% unburned fuel. If the gases were allowed to stay in the crankcase, they would quickly contaminate the oil and turn it to sludge. Sludge is one of the biggest enemies of your engine, clogging it up, eventually leading to expensive failures. Also, the pressure build up would cause seals and gaskets to blow out. Therefore, these gases need to be vented out.

Gasoline engines used to simply have a hose that let the poisonous fumes vent out into the air. In 1963, the federal government required gas engines to have a special one-way valve installed to help reduce dangerous emissions. Diesel engines are not required to have these valves.

The positive crankcase ventilation, or PCV, valve routes crankcase gases through a hose and back into the air intake system where they are re-burned in the engine. Fresh, clean air is brought into the crankcase through a breather tube. It’s really a pretty simple system, but does an important job. The re-circulating air removes moisture and combustion waste from the crankcase, preventing sludge. This extends not only the life of your oil, but the engine as well. The PCV relieves pressure in the crankcase, preventing oil leaks.

Eventually, the PCV valve can get gummed up. Then it can not move enough air through the engine to keep it working efficiently. If the PCV valve is sticking enough, you could have oil leaks, excess oil consumption and a fouled intake system. If you experience hesitation or surging or an oil leak, it may be a sign of PCV value problems. Your owners’ manual may give a recommendation for when the PCV valve should be replaced – usually between 20,000 mi/32,000 km and 50,000 mi/80,000 km. Unfortunately, some manufacturers don’t list a recommendation in the manual, so it can be easy to overlook.

Many PCV system problems can be diagnosed with a visual inspection. Fortunately, PCV valve replacement is both quick and inexpensive. Proper oil changes will greatly extend the life of the PCV valve. Skipping a few recommended oil changes can allow varnish and gum to build up in the valve, reducing its efficiency. So now when your Rowlett service technician tells you its time to replace your PCV valve, you will know what he’s talking about. If you have had your car for a while and this is the first you’ve ever heard of a PCV value, ask your tech to check yours out or call Lewis Complete Auto Repair at 972.475.4800.