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Tires, Suspension, and Steering

Power Steering Hose

Q: All of a sudden when I was driving I lost my power steering. I looked under the car and there was fluid dripping. What could be the problem and do I need any special tools to fix this?

A: Your power steering system has two hoses - a high pressure hose and a low pressure hose. The high pressure power steering hose may have burst. As for special tools, a flare nut wrench works best to remove the steel ended hydraulic line from the power steering pump. The flare nut wrench contacts the nut in more places as compared to a regular open ended wrench. This lessens the likelihood of rounding over the nut.

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CV Boot Torn

Q:  I recently had my oil changed at a quick lube shop and they told me that my CV boots are torn. The car still drives fine. Do I need to replace just the boots? How long can I drive my vehicle with a torn CV boot?

A: A torn CV (Constant Velocity) boot will provide dirt and moisture access to the CV joint and will allow grease, packed around the joint for lubrication, to escape. The longer the boot remains torn, the more likely your CV joint will fail. It really depends on how long the boots have been torn and whether or not the joints are damaged. The boots are designed to keep dirt and debris out of the joints and hold grease in the joints. If the joints are not damaged, the boots can be replaced and grease repacked. If you continue to drive the vehicle, the CV joints will continue to lose grease and become damaged. If the joints are already damaged you can have the joints replaced or each (driver’s and passenger’s) shaft replaced. The shaft, also called a CV half-shaft, comes with the inboard and outboard joints and boots as a complete unit. Although you may be able to drive for sometime before the joint breaks, the sooner you get a new CV boot the better. It is much less expensive to replace a CV boot than the whole CV joint or shaft. Normally you will begin to hear a CV joint click as it wears. A tow is required when a CV joint breaks.

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Checking Tire Pressure

Q: How often should I check the pressure in my tires?

A: You should check the pressure in your tires at least once a month. Use a high quality tire gauge. Always check tire pressure when the tires are cold. It is also a good practice to check the tire pressure before long trips. Be sure to inflate your vehicle's tires to the specifications found on the tire placard. Replace the valve stem caps after checking tire pressure.

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Tire Pressure Monitoring System

Q: What is a tire pressure monitoring system?

A: A tire pressure monitoring system is used to alert the driver if one tire or a combination of tires is significantly low on pressure. All passenger cars, light trucks, SUVs, and buses that have a gross vehicle weight ratio of less than 10,000 pounds and manufactured on or after September 1st, 2007 are required by the National Highway Traffic Safety Administration to have a tire pressure monitoring system (except dual wheel axle type vehicles). Automotive manufacturers have had several years to phase in this technology, so your vehicle may have a tire pressure monitoring system already.

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Tire Valve Core

Q: One of my tires is slowly leaking from inside the valve stem. Is there any way I can fix that without bringing it to a shop?

A: The valve core can be removed and replaced. You will need a valve core remover tool to unscrew the defective valve core. Wear safety glasses. Since the tire is under pressure, the valve core could go airborne when removing it. Replace the defective valve core with a new one. Tighten the new core snugly, but do not over-tighten. Valve cores and the valve core remover tool can be purchased at your local auto parts retailer. Remember to inflate the tire to the correct psi as indicated on the tire placard after installing the new valve core.

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Cheater/Extension Bar or Four-way

Q: Last weekend I had a flat tire. So I pulled over to the side of the road, got out my lug wrench, and attempted to loosen the wheel lug nuts. I could not budge the lug nuts with my L shaped lug wrench so I had to call a tow truck. He used a piece of pipe over the lug wrench handle and got them off easily. What can I do to prepare for the next time I get a flat?

A: Some people use a piece of pipe over the handle of a tool to extend the length. By extending the handle, you can exert more torque to the lug nut using the same force of your body (Torque = Force X Length). However, this can cause a hazardous situation. Sometimes the tool isn't engineered to handle that much torque and could break. Your best bet is to purchase a heavy duty four-way lug wrench. A four-way lug wrench is designed so you have two handles - one to push down on and one to pull up on. Each end fits different sizes of lug nuts. Standard and metric four-ways are sold, so be sure you buy one that works with your car. Find the end that snugly fits over your car's lug nuts and paint it a bright color. That way if you need it on the side of a dark road you will quickly see what end goes on the nut.

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Tire Valve Stems

Q: On my daughter's car her right front wheel valve stem continues to break. What could cause this? In the last year she has had several flats from torn valve stems.

A: If the valve stems are long and the tires rub the curb while parking, tire valve stems could tear. Also, when checking air pressure both hands should be used. Use one hand to hold the valve stem the other hand to push the air gauge. If she uses an air gauge and excessively pushes the valve stem to the side, the force could cause it to tear or weaken. Since it is the right front tire, her problem may be due to rubbing curbs. The solution would be to use short, steel tire valve stems that do not extend past the sidewall of the tire. Steel tire valve stems are very durable. You will need to take the car to a tire shop since each tire will have to be broken down to insert the new stem.

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Shocks/Struts Worn

Q: When I am driving and hit a small bump the car begins to bounce unsteadily. I actually have to slow up to control the bounce. What would cause this?

A: The shocks and/or struts on the vehicle may need replacing. Shocks are used on some vehicles, others use struts, while some vehicles use struts in the front and shocks in the rear. Shocks and struts are part of the car's suspension system designed to absorb bumps, keep the tires contacting the road, and stabilize the car in corners. Worn shocks and struts can cause a hazardous driving situation.

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Flat-spotting Tires

Q: After skidding to a stop with smoking tires my car now vibrates especially at higher speeds. What's wrong and how can it be fixed?

A: You probably flat-spotted your tires. During brake lockup, the tires wear on one spot. The tire gets out of balance and out of round when there is less tread on that part of the tire, causing the vehicle to shake at high speeds. You may need to replace the tires.

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Hit Curb with Wheel

Q: When I parallel park, I sometimes hit the curb. Will hitting curbs cause damage to my car?

A: Running into a curb could change the wheel alignment, loosen wheel weights, and damage the tires. When parallel parking, you should stay six to twelve inches from the curb. If you do hit the curb and then notice your steering wheel pulling one way during regular driving, have the alignment checked.

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Low Profile Tires

Q: What is a low profile tire?

A: Low profile tires are normally considered performance tires. However, they have become increasingly popular on many types of vehicles due to consumer demand for sportier looks on average cars. Low profile tires have short sidewalls and wide treads. Low profile tires are generally more responsive to driver controls, especially in cornering. Even though low profile tires provide a sportier look and improved handling, there are trade-offs. Since low profile tires have short and stiff sidewalls, the vehicle's ride is commonly more ridged as compared to tires with taller, more flexible sidewalls. They are also more expensive.

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Radial Pull

Q: My mechanic told me that my new tires had radial pull. He cross-rotated the tires and the pull went away. What is radial pull?

A: Radial pull can be caused by a defective radial tire construction or uneven tread wear. A misalignment of the belts inside the tire can cause a new tire to pull in one direction. Moving the bad tire to the back reduced its effect on steering. You may want to check into having the tire replaced under warranty.

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Shaking at 40 mph

Q: Traveling around 40 mph my car begins to shake. What do you think is causing this problem?

A: Shaking can be caused by tires being out of balance, broken belts in a tire, or worn suspension components. Tires that are out of balance can cause vibrations at different speeds leading to unsafe driving. Bring your car in to a tire service center to have your tires inspected and rebalanced.

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Shocks and Struts

Q: When my car was new it handled great around corners. Now it seems to be swaying and I feel like I have less control. What could be causing this?

A: Shocks and struts are used to make a vehicle's ride smooth and improve handling while driving. Shocks are used in conjunction with springs, whereas struts often combine the shock and spring into one unit. Your car will need new shocks or struts if fluid is leaking from them or your vehicle sways excessively around corners. Replace shocks and struts in pairs. Depending on the vehicle, you may need to have the wheels realigned after replacing the struts.

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Snow Tires vs. All-Season Tires

Q: Why are snow tires used if all-season radials are supposed to be good all year?

A: For many drivers, all-season radials will be sufficient. However, if you live in the snow belt and do a large amount of winter driving you may want to consider snow tires. Snow tires have a more aggressive tread and are more flexible than all-season tires. This gives snow tires superior traction in the winter. Even though an all-season radial may have a "M+S" (mud and snow) designation, it is not truly a snow tire. A certified snow tire will have a snowflake-on-a-mountain icon on the tire's sidewall. This designation identifies that the tire met strict standards during American Society for Testing and Materials (ASTM) snow tests.

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Speed Rated Tires

Q: I got a price quote on tires but the shop wants to know whether or not my tires are "T" or "H" rated. What is the difference?

A: Some high performance tires have speed ratings. Tires rated for higher speeds generally have rigid sidewalls. This type of construction increases the performance characteristics, but commonly reduces the comfort of the ride. In addition, the tread on a high speed performance rated tire is commonly soft to aid in traction. The softer the tread, the quicker the tire wears. "T" rated tires are rated for 118 mph and "H" rated tires are rated for 130 mph. Technically, speed rated tires are designed to be stable up to and at the rated limit. This does not mean that drivers should exceed posted speed limits.

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Speedometer and Tire Sizes

Q: I recently bought a used pickup. The truck has 265/75R16 tires, which are larger than the original equipped tires of 245/75R16. Can you tell me if these larger tires impact the accuracy of my speedometer or my braking potential?

A: If your vehicle has different sized tires than what the auto manufacturer recommends, you run the risk of having an incorrect speedometer and possible braking problems. The diameter of a 245/75R16 is about 30.46 inches, while the diameter of a 265/75R16 is around 31.64 inches (a 1.18 inch difference). The change in diameter changes the circumference, which in turn changes the revolutions per mile. This difference in circumference will affect your speedometer by about 3.9%. Since the truck was originally equipped and designed for 245/75R16s and now has 265/75R16s, at 60 mph your truck's speedometer would only read 57.7 mph, increasing the likelihood of getting a speeding ticket. Also, running too large of tires puts additional stress on braking components (e.g., brake calipers, rotors) that were designed to handle smaller tires.

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Steering Wheel Pulls to One Side

Q: What may cause my steering wheel to pull to the right while driving?

A: Your car is most likely out of alignment. Incorrect alignment reduces tire life and can cause unsafe driving. You should take your car to a tire shop or service center that specializes in wheel alignments. Correcting the alignment will increase fuel economy, improve handling, and extend tire life.

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Temporary Spares

Q: How fast can you drive on a temporary spare?

A: Most temporary spare tires are designed for a maximum speed of 50 mph. Only use this type of tire to reach a facility that can repair or replace your original tire. Before returning your spare to the storage location, check the air pressure. It is common that the air pressure in a temporary spare is higher than in your regular tires. Always read the owner's manual and tire sidewall for specific information.

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Tire Balancing

Q: Should I get my tires rebalanced every time I have them rotated?

A: You should get your tires rebalanced if you notice vibrations or if the tires are wearing abnormally. You should also get a tire rebalanced if it has been removed from the rim during repair. But to have the tires rebalanced every 7500 miles probably is not cost effective depending on the price of the tire. If you do not notice any vibrations or abnormal wear I would only recommend getting the tires rebalanced in the middle of their life - often this is at the 30,000 mile interval. And next time you buy a set of tires, look for a tire company that gives free rotations and balancing for the life of the tires.

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Tire Bead Leak

Q: I recently had four new tires installed on my car. The tires lose about 8 psi per week. Where do you think they are leaking and how can I tell?

A: The bead, where the rubber contacts the wheel, may be leaking on each tire. The best way to look for leaks is to put about a teaspoon of dishwashing soap in a spray bottle and fill with water. Spray the tire, rim, valve stem, and valve core with the soapy solution. As you spray the tire you will see many bubbles from the soap, but look carefully. Eventually the leak will start to blow a pile of bubbles. If the bead is leaking, you can have each tire broken down and the bead cleaned. Then the tire shop can use a special bead sealer to seal the tire.

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Tire Cracking

Q: What causes my motorhome and boat trailer tires to crack?

A: Ultraviolet light and ozone are the key factors that make tires crack. Tires that are not used frequently, like those on trailers and motorhomes, are more likely to crack than tires on your everyday car. Tire manufacturers include a wax-type component built into the rubber that releases as the tire is used. This component protects against ozone. The problem with motorhomes, boat trailers, and collector cars that don't get used often is that the wax isn't released. Tire manufacturers also include a component called carbon black to protect against ultraviolet (UV) light. To slow the cracking process, cover the tires when stored outside. Before storing for long periods of time, use a tire protectant that contains UV stabilizers.

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Tire Cupped

Q: What does it mean when tires are cupped?

A: The tread on the tire has abnormal wear. Cupping can be caused by improper tire balance, weak shocks or struts, or other worn suspension components. This abnormal wear occurs when the tire bounces slightly as it is rotating down the highway. To check your shocks and struts, complete a bounce test on the car. Push down on the end of the car that the tires are wearing abnormally and see what happens. The car should bounce back up and stop bouncing. If the car continues to bounce more than twice, the shocks or struts could be worn. Check both the front and back of the car. Remember to rotate tires every 7500 miles to maximize their life.

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Tire Leak Test

Q: How do you check for a slow leak in a tubeless tire?

A: Fill a spray bottle with a soapy water mixture. A small amount of dish detergent in water usually works well. Completely coat the tire by spraying the tread, the bead (the connection between the rubber tire and the rim), and the valve stem. A leak in the tire will start to blow little bubbles. Be sure to carefully check the valve stem and bead because they are common culprits for slow leaks.

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Tire Pressure and Mileage

Q: Does tire pressure really impact fuel economy of a vehicle?

A: Tire pressure can greatly impact fuel mileage. The correct tire pressure is a delicate balance between tire performance, tire life, ride, safety, and rolling resistance. The lower the rolling resistance the tire exhibits, the higher the fuel mileage. However, less rolling resistance also means less traction. Underinflated and overinflated tires can be dangerous. Purchase a high quality tire gauge and check your tires every time you fill up with gas. Inflate to the maximum pressure as designated on the tire placard usually located on the driver's door or door post.

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Tire Pressure and Temperature

Q: The pressure in my tires changes from when I park inside my heated garage to when I check them outside in the cold weather. What is going on here?

A: Generally, a tire's air pressure changes 1 psi (pounds per square inch) for every 10 degrees Fahrenheit (F) change in temperature. The air pressure goes up when the temperature increases and goes down when the temperature decreases. For example, if you have your car parked in a heated garage at 70 degrees F and then drive your car when it is 0 degrees F outside your tires may be as much as 7 psi too low. If you are checking the tires inside the warm garage, you need to adjust the tire pressure for what the temperature is outside. To do this, you need to add 1 psi for every 10 degrees F difference between the garage and outside.

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Tire Pricing

Q: I was pricing a set of tires and got confused. What should be included when pricing tires?

A: When pricing tires, make sure the service center includes mounting, balancing, disposal, and new valve stems. They may also give you the option to add or may include road hazard insurance. Road hazard insurance will cover the cost of repairing or replacing your tire if it is damaged during the warranty period. Always replace tires in complete sets or pairs.

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Tire Repairs

Q: Do you recommend using liquid tire sprays to fix a leaking tire?

A: I would only recommended using liquid tire sprays in emergency situations. The liquid can corrode the inside of the rim and throw the tire off balance. A better fix is to have the tire plugged or patched. A technician can plug a tire without removing it from the rim. However, when a tire is patched it needs to be removed from the rim. Always have the tire and wheel assembly rebalanced if the tire was taken off the rim during the repair.

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Tire Road Hazard Insurance

Q: What is tire road hazard insurance and how much does it cost?

A: Tire road hazard insurance can be purchased from your tire dealer when you purchase new tires. Some tire dealers and manufacturers include this in the cost of the tire, while others may charge around $10.00 per tire for the insurance. This covers the cost to replace the tire if it is damaged beyond repair. Road hazard warranty coverage is only valid if the tire has more than 2/32 of an inch of tread. In addition to the minimum amount of tread, some tire manufacturers have time limits like 3 or 5 years. Tires used on commercial vehicles are also not commonly covered. To fully understand what is covered, be sure to read the fine print.

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Tire Rotations

Q: My mechanic told me that I should rotate the tires on my car. What is the benefit of rotating tires and how often does this need to be done?

A: Rotating increases the life of the tires. Tires can wear differently from side to side and from front to back. Rotate tires every other oil change or at 7,500 mile intervals to even out the wear. Look in your owner's manual for specific procedures. If frequently rotated and properly inflated, tires should last about 50,000 - 60,000 miles.

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Tire Tread Depth Laws

Q: What is the minimum amount of tire tread allowed by the law?

A: Tires are commonly measured in 32nds of an inch. In most states, when a tire tread reaches 2/32nds of an inch it is legally worn out. Wear bars, which are set at 2/32nds of an inch, run from one side of the tire tread to the other. If the tread wears down to these bars, the tires need replacing. The less tire tread you have the more likely the car will hydroplane. Inspect your tires regularly to make sure they have plenty of tread.

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Tire Tread Depth Test

Q: How long do tires last and how can I tell when I need new ones?

A: New tires commonly last between 40,000 and 60,000 miles. This depends on the type of vehicle you drive, how often the tires are rotated, tire quality, and driving habits. If you ever see steel belts coming out of the tires replace them immediately. Tires are worn out when the tread is worn down to 1/16th of an inch. Tire wear bar indicators are placed in the tread to identify this depth. Tire stores will use a tread depth gauge to measure the amount of tread left on a tire. You can also use a penny to make sure your tires are OK. Turn the penny so Lincoln's head is closest to the tire. Place the penny, head first, in between one of the tread grooves. If you can see the very top of Lincoln's head, your tire is worn out.

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Torque Steer

Q: Why does my car pull one way when I accelerate hard into a curve? It is front-wheel drive.

A: What you are describing is torque steer. This is common on some front wheel drive vehicles. Torque steer is the tendency for the vehicle to pull to the right or to the left, especially when the engine is under full acceleration. Engine movements, differing constant velocity shaft lengths, nonsymmetrical shaft angles, worn suspension and steering components, and unequal traction on the road surface can cause torque steer.

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Torque Wheel Lug Nuts

Q: What does it mean to "torque" the wheel lug nuts?

A: To torque means to tighten the wheel lug nuts to all the same tightness. A torque wrench is needed to torque wheels to the correct setting. Over tightened lug nuts can distort the stud's thread, strip the lug nut, warp the brake rotor, weaken the fastener, and ultimately cause the stud to break causing an accident. Under tightened lug nuts may loosen up and cause the wheel to come off. Torque specifications are given in lb-ft (or Newton-Meters in the Metric System) and vary depending on the stud diameter and wheel design. Refer to your owner's manual for lug nut torque specifications.

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Wheel Alignment

Q: Should an alignment be part of regular maintenance?

A: I recommend getting an alignment when one or more of the following conditions occurs: the vehicle hit a curb or other obstruction; steering wheel is pulling one way or another; one or more tires are wearing abnormally; when replacing the tires; after an accident or going in the ditch; and, when suspension or steering components have been replaced. The correct alignment will increase the life of the tires, increase fuel economy, and provide for safer driving.

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