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 Los Angeles 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 California 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 http://www.rmauto.com/contact-us/ for more information.

What type of technology do you use? Do you prefer an 8-track tape or an iPod? When it comes to winter tires, much of the public’s perception dates back to when 8-track was the best way to listen to the Bee Gees.

Twenty years ago, winter tires differed from highway tires only in their tread design. We called them snow tires back then and they had big, knobby lugs that were designed to give good traction in deep snow. They had the same rubber compound as regular tires and they weren’t very good on ice, packed snow or wet roads. They were not even very good on dry roads. They really helped in deep or loose snow, but they did a poor job the rest of the time. They were loud and rode hard. You couldn’t wait to get them off in the spring.

Then all-season tires started to come along. All-season tires are really a compromise between summer and winter performance. They have acceptable hot weather ride and tread life, and you can get through mild winter road conditions OK. But there are some really good reasons to consider winter tires.

Modern winter tires do a terrific job in a wide range of winter conditions. First of all, below 45 degrees Fahrenheit, regular tires become hard and inflexible. That means they don’t provide the road grip you need. Even if you don’t live somewhere with a lot of snow, but it still gets below 45 degrees in the winter, you will be safer with winter tires.

In addition, they are specifically designed to more effectively move snow and water. That’s the key to traction on ice, packed snow and wet roads. They use a micro-pore compound that allows the tire to bite into ice and snow. They also use wider grooves that run around the circumference of the tread to expel snow from the tire better. The lugs and grooves on winter tires have a special shape that throws the packed snow out of the tread as the tire turns. The tread is then open when it comes back in contact with the road and can provide good traction.

Winter tires also have a lot of sipes. Sipes are thin slits in the tread. The edge of the sipes grab ice and packed snow to provide tons of traction and to expel water and slush out of the tread. winter tires have a rounder casing to cut into the snow’s surface. The treads on regular summer tires can actually get packed with snow instead and become very slick. winter tires offer 25% to 50% more traction than all-season tires. And when it comes to stopping power, all-season tires take 42% longer to stop than winter tires. Sometimes that’s the difference between getting home safely and spending the night in a snow bank.

Now back when the 8-track was king, you just put snow tires on the drive wheels. That worked out OK because the rubber compound was essentially the same. Now, winter tires provide so much more traction than all-season or summer tires, that there’s a huge difference between the traction at the front and rear ends of the car if you only put winter tires on the drive wheels.

For example: if you take a corner on an icy road and the rear end starts to slide out, essentially the rear is trying to pass the front because it’s going faster. If you have high traction winter tires only on the front, they are going to be much more effective at transferring cornering grip and stopping power to the front wheels. This will actually cause the rear end to whip out even more.

That’s why tire manufactures instruct their dealers that they must install winter tires on the rear wheels as well whenever they put winter tires on the front end of any vehicle. It’s a major safety concern. It’s strongly recommended that winter tires be installed on all four wheels on rear wheel drive vehicles as well. The front tires do most of the steering and braking work – it only makes sense that you provide the front end with the best traction you can.

People often assume that if they have four-wheel drive or all-wheel drive they don’t need winter tires on all four wheels. Would you intentionally disconnect the four-wheel drive in poor road conditions? Of course you wouldn’t, but that’s essentially what you do if you only put winter tires on one end. It only makes sense to have the same level of traction and control at all four corners.

The province of Quebec in Canada has issued a law requiring all passenger vehicles, taxis and rental cars with Quebec license plates to install a full set of four winter tires between November 15th and April 1. It’s that important.

Many modern cars have traction control and anti-lock brakes so people may think that they don’t need winter tires. But you need traction to accelerate, steer and stop. The tires provide the traction so that the traction control and anti-lock brakes have something to work with.

Look for tires with the symbol of a mountain with a snowflake in it. This means the tire complies with the severe snow standard. All-season tires will have an M&S, for mud and snow, on the sidewall.

So when the temperatures drop below 45 degrees, be sure you have a set of four winter tires for maximum performance in snow, packed snow, ice, wet and dry roads. Your tire professional can help you find the right winter tire for your vehicle and driving needs.

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.

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 a Northridge service center such as RM Automotive 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 service center where they 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 Northridge service center to do things right.

Remember, RM Automotive has the equipment to change your coolant quickly and inexpensively. (818) 709-4343

A lot of our viewers have asked whether or not they should use their severe service maintenance schedule, which is listed in their car owners’ manual. It can be confusing. Let’s clear the air on this subject. Cricket Killingsworth is from QMI/Heartland, a manufacturer of automotive products and fluids. She’s been in the automotive business for 20 years and is a speaker, a trainer, and a writer. Cricket says there’s so much confusion on this topic because, “Most owners’ manuals actually have two maintenance schedules. Sometimes these are called ‘regular service’ and ‘severe service’. Sometimes they’re simply called Schedule 1 and Schedule 2. A severe service schedule recommends that things like an oil change, air filter replacement, and transmission service be done more often: either in fewer miles or in less time.

Manufacturers create these specific schedules for each vehicle they make. So there isn’t one generic schedule that applies to all cars. In addition to your owners’ manual, Northridge automotive repair centers subscribe to information services that provide the maintenance schedules for every vehicle – so they can help you know when to take care of needed services. Below is a typical definition for severe service.

• Most trips are less than four miles
• Most trips are less than ten miles and outside temperatures are below freezing
• You drive in very hot weather
• The engine is at low speed most of the time (not on the highway)
• Stop and go driving
• You operate your vehicle in dusty or muddy conditions
• You tow a trailer, regularly carry heavy loads or carry a car-top carrier

It’s common sense: Just a few minutes at freeway speeds allows the moisture in the oil to evaporate. Very short trips, or trips of less than ten miles when it’s very cold, don’t allow the engine to heat up enough to get rid of the water. And water in the oil leads to damaging sludge. Also, towing and heavy loads raise operating temperatures and cause fluids to breakdown more quickly. Dusty and muddy driving means that more dirt will get past the air filter to contaminate the fuel system and engine oil.

The bottom line is that you need to decide for yourself if the regular or severe service schedule is right for you, based on your driving. Look at your owners’ manual, or talk with your RM Automotive service advisor who can help you know which schedule to follow. RM Automotive is located at 19248 Roscoe Blvd., Northridge California.,

Here is what a fleet manager said recently: “Since city miles are generally tougher on vehicles than highway miles, we use the manufacturer’s severe service schedule as the basis for our preventative maintenance program. We massage those schedules over time, increasing or decreasing the service intervals so that they make the most sense. There is a little bit of art to go along with the science.

Make an honest evaluation of your driving habits. Unless you do mostly California highway driving in moderate weather, you’ll likely have a fairly good amount of severe service mixed in. Some people just want to play it safe and follow the severe service recommendations, rather than analyzing how they drive each month.

When you hear the word ‘suspension‘, you may think back to those energetic days of grade school. Well, your car’s suspension is actually a good thing because it keeps your car up off the road and helps provide a comfy ride. It needs to keep your wheels firmly planted over bumps and through curves. Your suspension system has many parts. If you look under your car, it’s basically everything that connects your wheels to the car’s frame. These are heavy duty parts that do a lot of work. They need to be inspected for damage and excessive wear at least once a year. A good time for this is when you get your annual alignment service.

Here are some warning signs that your suspension may have problems:

• the car pulls to one side;
• it wanders;
• the steering is erratic;
• you see uneven tire wear;
• you experience a poor ride or handling;
• you see oil leaking from shocks

. . . you get the picture. You just don’t feel in control when you’re driving.

Some suspension parts just wear out with use. Shocks and struts eventually lose their ability to control your ride. Wheel bearings need to be repacked every couple of years. And some suspension pieces need to be lubricated when you get your oil changed. Your service advisor can oversee an inspection and tell you what problems you may have.

If you’re in an accident, your suspension can be damaged or knocked out of alignment. Even a minor accident, like hitting a curb around Northridge or even a large rock can mess things up. With a minor accident it’s tempting to just get an alignment or wheel balance to correct the problem. But if there’s some damage, a simple alignment won’t actually fix the problem, and you’ll just have to align it again after the repairs are made. So if you have an accident, get your suspension system inspected right away. Suspension problems should be fixed immediately because they can lead to unsafe handling.

One big cause of suspension damage is potholes – those nasty magnets that seem to draw our tires right into them. Here are some tips for avoiding damage from potholes: First, keep your tires at their full air pressure. That gives tires their maximum resiliency and will hopefully keep your wheels or other suspension parts from crunching on a big hole. Next, just pay attention. When you see a hole you can’t miss, slow down before you hit it. Driving at a slower speed will limit the damage, and may keep your drink from spilling. But don’t brake directly over the pothole. That will cause the car’s weight to shift forward and add to the potential damage.

So don’t put off an inspection of your suspension. We promise the principal won’t be involved.

RM Automotive
Give us a call today at (818) 709-4343.
Or stop by at 19248 Roscoe Blvd., Northridge, California 91324

North Americans love their cars. And nothing goes with cars better than the road trip. Freedom from daily schedules, new sights and the open road – it’s great! But there’s nothing like car trouble to bring the fun to a grinding halt.

Now you can’t always avoid problems, but you can take steps to reduce the probability of getting sidelined on your trip. The first step is to look at your trip plan from your vehicle’s perspective. What kind of roads will you be traveling – winding byways or super-highways? Mountains or plains? What weather conditions are you likely to encounter? How many miles will you travel? How much weight will you be hauling – passengers and luggage? Lugging a trailer or roof top carrier? Will it be dusty?

Armed with the answers to these questions, you can start a trip inspection to help you prepare your Northridge vehicle for your big adventure. A lot of our Northridge customers prefer to go through this exercise with an automotive service advisor at RM Automotive to get their input and make sure they haven’t left anything out.

A great place to start is with the tires. Inspect them for tread wear and proper inflation. Is it time to rotate your tires? Replace them? Are they up to the job – you wouldn’t want to drive regular highway tires on a muddy off-road adventure.

Shocks and struts play a major role in both driving comfort and safety. If they need to be replaced, you’ll really be glad you did once you hit the road. Is it time for a wheel alignment? Fighting a car that’s pulling to one side all day can be tiring and dangerous.

And don’t forget your brakes. Any strange noises, grabbing, soft or hard peddle feel? If there is any doubt, get a brake inspection before you leave.

Moving under the hood, have your belts and hoses inspected. If something is excessively worn or near failure, the stress of a long road trip might just be the straw that breaks the camel’s back.

Your engine air filter will be important. For every gallon of gas you burn, your car will filter and use 12,000 gallons of air. If the filter needs to be changed, you’ll notice the fuel savings on your trip.

How close are you to your next oil change? Will you be able to complete your trip before it’s due? If not, just get it taken care of before you go so that you don’t need to interrupt your trip. In fact, a full service oil change is a great idea because they will top off all your fluids and check to see if any other maintenance items are due, such as transmission or cooling system service.

Do you notice any unusual odors in your vehicle? If so, it could as harmless as a dirty cabin air filter. But if it’s an exhaust leak it could be fatal on a long trip. Of course you’ll want to be comfortable, so get an air conditioning service if you aren’t getting the cold air you used to.

Are you wiper blades still working well? If not, that is quick and inexpensive to fix. Headlamps are often overlooked when planning for a trip. If you haven’t changed the bulb in six months or so, replacement bulbs will really light up the night on your trip.

All the items mentioned are part of any good vehicle maintenance plan. These are things that you want to take care of anyway, but they all come into focus as you plan for your trip.

They will always save you money in the long run and may prevent inconvenient delays on your trip. After all, you wouldn’t want to miss the world’s largest ball of string, would you?

We would like to give you an update on some of the things happening in automotive fluids. You know, cars are becoming more sophisticated everyday – and fluids such as, oil, coolant and transmission fluid are becoming more specialized at about the same pace.

The do-it-yourselfer has to be pretty careful so that they do not actually harm their vehicle with the wrong type of fluid. That is why so many California car owners rely on the advice of their service consultant to not only get the correct family of fluids, but to suggest the formulation that is best for their car and the way they drive.

Let’s start with engine oil. If you have been paying attention, you will have noticed a number of new oil weights on the scene in the last several years. Modern engines are built to much tighter tolerances and have very complicated valve trains. The oil must be thin enough to lubricate complicated parts when the engine is cold. The weight of an oil is expressed in terms like 20-W-50 or 5-W-30. Manufacturers recommend the weight of oil for each vehicle they make. The recommendation is based on engine design. Your Northridge service center will know what weight your manufacturer recommends – and it’s important to follow those recommendations. A service adviser at RM Automotive can also offer suggestions for special formulations and can explain conventional and synthetic oils.

Antifreeze, or engine coolant, is another area that has become more complicated. For a long time, manufacturers only called for a couple of different types of coolant. Now there are several different formulations that are needed because of the different materials that manufacturers are using to build the cooling system. Using the wrong type of coolant can actually void your warranty, so you want to get that right.

Transmission fluid is beginning to be specialized as well. New transmission designs have particular requirements that mandate the use of specific formulations. Recently, new, somewhat confusing, standards for brake fluid have also been released.

Not too long ago, there was a good chance that all of the vehicles at your house would use many of the same fluids. However, as automotive technology advances, the array of basic automotive fluids you need will grow. And, some of the formulations will cost a little more. Fortunately, your Los Angeles service center will continue to update their training to keep pace with technology so that you’ll get the right fluids your car needs. It’s all part of the commitment your service center makes to your driving peace of mind.

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 Northridge 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 RM Automotive 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 RM Automotive at (818) 709-4343 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.

Do you hear loud noises under the hood when you turn on your air conditioner? Do you only get cool air sporadically? If so, it is time to get your air conditioner checked. It’s real easy to take your car’s air conditioner for granted. Just push the right buttons and out comes cool, dry, clean air. But your air conditioning system needs attention from time to time to help it keep its cool.

When most people hear the words “air conditioning problems”, it sends a shiver up their spine. That is because the air conditioning system is fairly complex. It has a lot of parts and when it’s broken, it’s expensive to repair.

What things can we do to prevent air conditioning breakdowns?

A common cause of air conditioning failure is leaks. Water and air can leak into the system. The system doesn’t work as well with air in it. And water can cause rust that leads to damage of the A/C components. Also, refrigerant, the stuff that makes the air cold, can leak out, reducing the efficiency of the system, making it work harder to cool the air. Periodically evacuating the air conditioning system and recharging it keeps the proper amount of clean refrigerant in the system so it cools better and lasts longer.

You should also run the air conditioner regularly, even during California winters, so that it lubricates itself and keeps the seals from drying out, which leads to leaks. Your owner’s manual will have recommendations for how often to service your air conditioner. Of course, if it’s not working right, now is the time to get it checked. Many Los Angeles service centers can inspect and test your air conditioning and offer evacuation and recharge services. We recommend RM Automotive in Northridge. See http://www.rmauto.com/contact-us/ for address and phone number. A quick inspection can help you avoid having to bring your air conditioner in for major repairs.

New environmental laws have stopped the manufacture of Freon, a refrigerant that was common in cars made before 1993. There is a very limited supply of Freon so the price is very steep. It may not be worth its weight in gold, but it probably is worth its weight in silver. If you have an older vehicle that uses Freon, you may want to consider having it retrofitted to use the new R134-A refrigerant. It will pay for itself in the long run. So, if your AC is just a lot of hot air, take it to a Chatsworth automotive service center for an inspection.