If you’re like most of us, you want your car to handle well. That’s the job of your suspension system.
There are different types of suspension systems, but they all work on the same basic principles. First, there are the springs, which bear the weight of the car. The most common springs are coil or leaf – although we see air springs and torsion bars more often. The springs do most of the work.
But if all you had were springs, your vehicle would be bouncing around like a bobble head. That’s where the shocks come in. They control the rebound of the springs and smooth out the up and down motions. They also keep the tires on the road, and you in control. Some cars use struts. Struts are a combination of shocks and springs, together in a more compact system.
Shocks wear out slowly over time, so it’s hard to notice when they get badly worn. One way to tell is to look for an uneven, cupping wear on your tires. If the shock or strut is leaking fluid, it needs to be replaced. If your car feels floaty in turns or if the front end dips a lot when you stop, it is time to get your shocks checked. Your owners’ manual will tell you when your shocks should be changed – it’s usually between 15,000 and 30,000 miles or 24,000 and 50,000 kilometers .
When you replace a shock, be sure to replace all four. Then your car will have an even suspension and will handle much better. Talk with your service advisor about how you drive. No, not your traffic violations, but how often you carry heavy loads, tow a trailer or drive in rough terrain. If you do a bunch of that, you’ll need a heavy duty shock.
Regular shocks use hydraulic fluid and air as their dampening system. Premium quality shocks and struts use compressed nitrogen gas instead of air. Gas shocks don’t get air bubbles that affect the performance of regular shocks. If you do a lot of high performance driving, off-roading or just want added comfort and control, think about getting premium gas shocks or struts.
Replacing your struts may take your car out of alignment, so be sure to get an alignment at the same time. So, to smooth out the bumps on the road of life, change your shocks and struts when they need it.
Ever heard the sad tale of a staggering repair bill from a broken timing belt? Bad news. Let’s take a lesson from their woes and remember to think about our timing belt.
First, let’s review what a timing belt does. The top part of the engine, over the cylinders is called the cylinder head. The head contains the valves. There’s at least one valve that lets the fresh air into the cylinder. This air, mixed with fuel, burns to create power. Then another valve or two open to allow the exhaust out of the engine. Each cylinder has 2 to 4 valves – that’s 12 to 24 valves for a V-6, up to 32 values on a V-8. The opening and closing of the valves is done by a camshaft. The timing belt uses the rotation of the engine to drive the camshaft which opens and close the valves. It’s called a timing belt because it has to be adjusted to rotate the camshaft to keep proper time with the engine so that everything’s in sync.
The timing belt is a toothed rubber belt . But some cars use a timing chain or timing gears instead of a belt. Timing chains and gears are much more durable, but manufacturers are using belts more because they are quieter – and cheaper. If you have a small or mid-sized passenger car, crossover or mini-van, chances are you have a timing belt.
Unfortunately, timing belts fail without any warning. That shuts you down right away. A technician can inspect your timing belt and look for cracks and looseness. But getting to the belt to take a look can be almost as much work as changing it on some cars. That’s why manufacturers recommend replacing the belt from time to time. For most vehicles it’s from 60,000 to 90,000 miles or 95,000 to a 145,000 kilometers. If your owners’ manual doesn’t specify an interval ask your service advisor.
One AutoNetTV producer has had two timing belts fail. The first was while he was waiting at a stop light – that repair cost several thousand dollars. The second was while driving on the highway – that one cost more than twice as much. Both had the cars out in the shop for three weeks. His cars had what we call “interference engines”, meaning that the valves and pistons are very close to each other. If the timing belt slips even one notch, the pistons will slam into the open valves. That’s why our friend’s highway failure was so much more expensive – his engine was traveling so fast that the valves were smashed and they chewed up the cylinder head.
A non-interference engine will just shut down if the timing belt breaks. You’re stranded, but the engine doesn’t suffer permanent damage. In both cases, our hapless friend was just a couple oil changes past the recommended interval for changing the timing belt. This is one of those things that you just cannot put off. Now replacing a timing belt is not cheap – but repairs for a broken belt can be many times as much.
Check your owners’ manual right away – especially if you have more than a 60,000 miles or 95,000 kilometers. You may need to get that belt replaced right away. And on many cars, the timing belt drives the water pump. So, it may be a good idea to replace the water pump while you’re at it because 90% of the work required for the new pump is already done with the belt change. Doing both at the same time saves you a lot of money because as they say, “timing’s everything”. Parts, Timing Belt
We all know that under inflated tires wear out more quickly. Under-inflation is also a major cause of tire failure. More flats, blow outs, skids and longer stopping distances are all results of under-inflated tires.
It’s hard to tell when a radial tire is under-inflated. If your manufacturer recommends 35 pounds of pressure, your tire is considered significantly under inflated at 26 pounds. The tire may not look low until it gets below 20 pounds.
Uncle Sam to the rescue! A new federal law requires manufacturers to include a Tire Pressure Monitoring System – or TPMS system – in all vehicles by the 2008 model year.
Some 2006 and 2007 models already have TPMS. The system is a dashboard mounted warning light that goes off if one or more of the tires falls 25 % below the manufacturer’s pressure recommendations.
The law covers all passenger cars, SUVs, mini vans and pick up trucks. The system must also indicate if it has a malfunction. This technology has been used by race cars for years. They are able to head off problems from under inflation by closely monitoring tire pressure on the track. It’s up to your car’s manufacturer to determine which of many TPMS systems available they’ll use to comply with the law.
Obviously, all of this doesn’t come free. Government studies have estimated the net costs. Of course, the TPMS system itself will cost something. Maintaining the system will have a cost, replacement of worn or broken parts and tire repair cost increases. The net cost is estimated to be between $27 and $100.
The costs are partially offset by savings in fuel and tread wear. There is also a saving in property damage and travel delay. Also, the government predicts fewer fatal accidents. They estimate there will be between $3,000,000 to $9,000,000 for every life saved.
Your safety has always been a concern of your service center. They want you on the road and accident free. They’ve traditionally provided things like tire rotations, snow tire mounting and flat fixes at a very low cost. They’ve been able to quickly and cheaply provide the service, and they pass the low cost on to you as an expression of their good will. That’s why they’re concerned about how you’ll perceive the changes that this new law will force.
Every time a tire is changed: taken off to fix a flat, a new tire installed, or a snow tire mounted, the service technician is now going to have to deal with the TPMS system. Sensors will need to be removed and reinstalled. The sensors will have to be re-activated after the change. And, unfortunately, the very act of changing the tire will damage some sensor parts from time to time – it’s inevitable and can’t be avoided.
Even a simple tire rotation will require that the monitor be reprogrammed to the new location of each tire. When a car battery is disconnected, the TPMS system will need to be reprogrammed. TPMS sensor batteries will need to be changed and failed parts replaced.
And the service centers themselves will need to purchase new scanning equipment to work with the TPMS sensors and to update expensive tire change equipment to better service wheels equipped with the new monitoring systems.
Service technicians will have to be trained on many systems and new tire-changing techniques. All of this adds up to significantly increased cost to the service center to perform what was once a very inexpensive service for you. So when you start so see the cost of tire changes, flat repairs and rotations going up, please keep in mind that it’s because of government mandated safety equipment. Your service center just wants to keep you safely on the road – and it’s committed to do so at a fair price. The effects of the new law will take some time to sort out, but it will help you avoid the most common vehicle failure, and possibly a catastrophic accident.
You know you need new tires, but you’re not sure what type. You look at a tire to get the size: 225, 50, R, 16, 92, H. All the way to the service center you keep repeating it over and over. You even say it over in your mind while waiting in line. Then you get to the counter and the manager asks what size you need. Then your mind goes blank.
Tire size can be confusing. There’s so much on the side of the tire, and it’s hard to keep straight.
Even though there’s a lot on a tire – if you know what it all means, it’s actually more helpful than confusing. Let’s start with the size number.
For example, let’s say a tire reads: 225 50 R 16 92 H. The 225 part is the width of the tire in millimeters – the width between the sidewalls of an inflated tire with no load. The 50 is the aspect ratio – the ratio of the sidewall height to the tread width. Off-road tires will have a higher number and high performance tires will have a lower number.
The R signifies it’s a radial tire. And 16 is the rim or wheel size in inches.
The 92 is the load rating index – it’s the load carrying capacity of a tire. The higher the number, the more it can safely carry. Your empty vehicle can be safe with a lower number, but you’ll need a higher rating if you routinely haul heavy loads. The next letter is the speed rating. Not all tires are speed rated. The ratings generally follow the alphabet: the further up the alphabet, the higher the speed rating – with the exception of H – it comes between U and V (don’t ask why).
There’s a lot of fine print that you probably need a magnifying glass to read. But there are a couple of other large print items of interest. One is the tread type: highway, mud and snow, all season, severe snow, etc.
And then there’re the Uniform Tire Quality Grading System markings. The first is a tread wear index. 100 is the base line – a lower number is poorer and a higher number is better. All things being equal, a tire rated 200 would wear twice as long, on a government test track, than one rated at 100. These wear grades are only valid within a manufacturer’s product line – you can’t compare with other manufacturers. And it’s important to note that a lower rating might be just what you want – a high performance, sticky tire has a softer rubber compound and won’t wear as long, but boy, will it take those corners.
The next is a traction grade. This measures the tire’s ability to stop on wet pavement in government tests. A – the best, B – intermediate, C – acceptable.
Temperature grade measures a tire’s resistance to heat build up in government tests. A, B and C – from best to acceptable.
It’s safe to go with the original equipment recommendations that came on your car. But if you want to make adjustments, you’ll now be better equipped to communicate with your tire professional.
At AutoNetTV we love doughnuts. So let’s pretend you have three doughnuts right in front of your for our discussion of upsizing wheels and tires. Hey, don’t eat them now – your going to need them later.
Many people want to accessorize their car – you know, make it theirs. One of the easiest ways to get a custom look is to get some new wheels. There are thousands of wheel designs out there to get you the look you want. And for many, that look includes bigger wheels. It used to be that cars came from the factory with 15 or 16 inch wheels. Now 16, 17 and even 18 inchers are standard. And the factories are offering optional wheel packages up to 20 inches or more.
So let’s talk about what to consider when you want to upsize your wheels. It’s not exactly a do it yourself project, so you need to know a thing or two before you get started. The most important term to know is rolling diameter. The rolling diameter is simply the overall height of your tire. Unless you want to modify your suspension, you’ll want to keep your rolling diameter the same when you upsize your wheels.
Let’s think about those three golden doughnuts in front of you. They’re all about the same size. So if we pretend they’re tires, they would have the same rolling diameter. The doughnut hole is the size of the wheel. Now pretend we’ve made the hole bigger on some. That’s like having a bigger wheel – but the rolling diameter is the same.
It’s important to keep the rolling diameter the same for several reasons. First of all, if the tire is bigger, it might not fit in the wheel well. Next the speedometer, odometer and anti-lock brake system are all calibrated for the factory rolling diameter. In order for your anti-lock brakes to work properly, the rolling diameter must stay within 3% of the factory recommendation. If you ignore that, you run the risk that your anti-lock brakes won’t work properly.
Some cars today have electronically controlled suspension that will be negatively affected by changing the rolling diameter. Let’s think about the doughnuts again. You see, as the size of the wheel gets bigger, the sidewall gets shorter. The tire holds less air, so the sidewalls are made stiffer to compensate.
Low profile tires from top manufacturers use special compounds that give the sidewall the strength it needs without compromising ride quality. As you increase your wheel size, you’ll typically get a slightly wider tire. This means that you have a larger contact patch. The contact patch is part of the tire that contacts the road. Because there’s more rubber on the road, the vehicle will handle better. And braking distances will be shorter. A lot of people with trucks or SUV’s love the extra control.
You do have to watch out that the contact patch isn’t so big that the tires rub in turns or over bumps. What we’re talking about here is fitment. Your tire professional can help you get this right. He’ll install your new wheels, add spacers if needed to make sure your brakes fit inside your new wheels, and get you rolling.
Also, if you drive off-road a lot, you may need a higher profile tire to protect your new rims. And make sure your new tires have the load rating you need if you tow a trailer or haul heavy loads. Again, your tire professional knows how to help.
And don’t forget about tire pressure. If you have larger rims, your new tires will hold less air and they’ll need to run a slightly higher pressure. Forget that and you’ll wear your tires out fast. Finally, get an alignment after you get your new shoes. AutoNetTV wants you to safely have the look you want.
So you love our job, and your family life is great: You have achieved balance. But can you the same for your wheels? You can tell if your tires are out of balance by vibrations at higher speeds. If one of the front tires is out, you feel the vibration in the steering wheel. If it’s a back tire, you’ll feel the vibration in your seat.
Tires and wheels are pretty heavy. When a tire is mounted on a wheel, it is usually not perfectly balanced. So the tire technician will spin the tire on a machine to determine where it’s too heavy. He will then place weights on the wheels in strategic locations to balance it out. When a tire is out of balance, it actually bounces down the road instead of rolling smoothly. Since the average size tire rotates at about 850 revolutions per minute at 60 MPH, it is actually slamming into the pavement 14 times a second. That’s where you get your vibration.
Most people are surprised at how smoothly their car rides after balancing all four wheels.
Most high-quality tires hold their balance pretty well. They just get out of balance gradually with normal wear and tear. If you suddenly feel a vibration, it is probably because you lost a wheel balancing weight along the way. Definitely get a balance if you feel a vibration, change your rims or have a flat repaired. Putting off a needed balance job leads to excessive tire wear, wear to your shocks, struts, steering and suspension parts. wheel balancing not only improves your ride and handling, but also can save you some big repair bills and possibly an accident. Additionally, you will get better gas mileage.
Some people have their tires balanced at every rotation. Others do it every other time. Check your owners’ manual for your requirements, or ask your technician. Doing thus will put you on the path to mechanical wheel balance
When winter approaches, we break out the sweaters, coats, boots and mittens. We want to be ready for winter conditions. Your vehicle needs to be ready for winter as well. The last thing you want is to get stranded out in the cold. You need your vehicle to be safe and reliable. It’s a good idea to get caught up on any neglected maintenance items anytime – but the stakes are higher in the winter.
There are some specific things that we need to do to have our vehicle ready for winter. The most obvious is having the antifreeze checked. If the antifreeze level is too low, it can’t properly protect your engine, radiator and hoses from freezing. If your car does not seem to be making enough heat to keep you warm, your antifreeze level may be low or you could have a thermostat problem. Get it checked out. If you are due for a cooling system service, now is a perfect time to have it done.
In the cold months we always worry about being able to stop in time when it’s slick out. The first thing to remember is to slow down and allow yourself plenty of room to stop. Of course, you want your brakes to be working properly. A thorough brake inspection will reveal if the pads or any other parts need replacing. Check with your service consultant to see if it is time to replace your brake fluid. It accumulates water over time which really messes with your stopping power.
It is a really good idea to have your battery tested. A battery’s cranking power really drops with the temperature. If your battery is weak in the fall, it may not be up to winter. There is nothing like a dead battery in a snow storm.
Which leads us to an emergency kit. You should always have a blanket or something to keep you and your passengers warm if you get stranded. If you will be venturing away from civilization, pack more items such as food and water to help you survive. Keeping at least half a tank of gas is a good precaution if you get stuck and need to run the car to keep warm and it will help keep your gas lines from freezing up.
Winter always makes us think of our windshield wiper blades – usually during that first storm when they aren’t working right. That’s why it’s a really good idea to replace your blades in the fall before the winter storms. If you live where there’s a lot of snow and ice, you might want a special winter blade that resists freezing up. And be sure to have enough windshield washer fluid.
The final thing to consider is your tires. Any tire can lose pressure over time – up to one pound every six or eight weeks. For every 10 degrees the temperature drops you lose another pound of pressure. So if it was 80 degrees outside when you checked your tire pressure two months ago and now it’s 40 degrees out, you could be down 5 pounds of pressure. That’s enough to be a real safety issue and it wastes gas too. You may need special winter tires as well. Your tire professional can help you find the right tire design for your expected road conditions.
If you’re getting winter tires, it is always best to put them on all four wheels. If you are only getting two, have them put on the rear – even if you have a front-wheel drive or four-wheel drive vehicle.
This is a very important safety measure recommended by tire manufacturers. Sliding or fish-tailing on ice and snow is a matter of not having enough traction at the rear end. That is why your newest tires should always be on the rear.
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.
Let’s talk about transmission service. It can be easy to forget about getting your transmission serviced because it doesn’t need it very often. It’s easy to remember to change the engine oil – you know, every 3,000 miles or 5,000 kilometers. But proper transmission servicing keeps your car running smoothly and helps you avoid costly repairs down the road.
The transmission undergoes a lot of stress. The grit you see in used transmission fluid is actually bits of metal that wear off the gears in the transmission. In addition to that, the transmission operates at very high temperatures. Usually it’s 100 to 150 degrees higher than engine temperatures. Those high temperatures eventually cause the transmission fluid to start to break down and loose efficiency.
As the fluid gets older, it gets gritty and doesn’t lubricate and cool the transmission as well – leading to even more wear. The fluid can actually get sludgy and plug up the maze of fluid passages inside the transmission. At best, your transmission won’t operate smoothly. At worse, it could lead to costly damage.
When your transmission is running properly, it transfers more power from your engine to the drive wheels, and improves fuel economy. That’s why manufacturers recommend changing your transmission fluid at regular intervals. Your owner’s manual has a schedule for transmission service and, of course, your service center can tell you what the manufacturer recommends.
Hot and dusty conditions; towing, hauling, stop and go conditions and jack rabbit starts all increase the load on the transmission and its internal temperature. That means you need to change the fluid more often. A good rule of thumb is every 35,000 miles, 55,000 kilometers or two years. If your manufacturer suggests more frequent intervals or if you’re driving under severe service conditions, you will need to change it more often.
Most service centers have the ability to perform a transmission service while you wait and the cost is quite reasonable. It’s downright cheap when you think about how much a major transmission repair can cost! Your service technician will know the right type of transmission fluid to use. If it’s getting to be time to have your transmission serviced, do your car a favor and have it done. If not this time, then on your next service stop.