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When are tires worn out? 

According to most states' laws, tires are legally worn out when they have worn down to 2/32" of remaining tread depth.

To help warn you that your tires have reached that point, tires sold in North America are required to have molded indicators called "wear bars"

across their tread pattern from their outside shoulder to inside shoulder. Wear bars are designed to visually connect the elements of the tire's tread

pattern and warn drivers when their tires no longer meet minimum tread depth requirements.

However, as a tire wears it is important to realize that while its dry traction and handling will improve, its ability to perform in rain and snow will

diminish. At 2/32" of remaining tread depth, resistance to hydroplaning in the rain at highway speeds has been significantly reduced, and traction

in heavy snow has been virtually eliminated.

If you plan to drive in wet weather, you should consider replacing your tires when they reach approximately 4/32" of remaining tread depth. Since

water can't be compressed, you need enough tread depth to allow it to escape through the tire's grooves. If the water can't escape fast enough your

vehicle's tires will be forced to hydroplane (actually float) on top of the water, losing traction.

How many tires should I buy? 

 Just one tire?

If your tires have a lot of remaining tread depth, but you need to replace just one damaged by an accident, road hazard or a vandal, you should

replace it with a tire that matches the others exactly. That means getting a replacement tire of the same brand, model, size and speed rating. Tires

that are not the same will not handle the same. You may not notice the difference during casual driving, but during emergency braking or evasive

maneuvering the car may not handle the way you want it to. Some cars like Subarus and Honda CRV 4wd have very specific requirements for

matching tread depth on all four tires.

A pair of tires?

If two of your tires have a lot of remaining tread depth, but you need to replace the other two because they were damaged or worn out, you should

replace them with a pair of tires that come as close as possible to matching your existing tires. While identical new tires are desirable, others of the

same size and type can also provide good results. Only consider selecting new tires that are from the same tire category as your existing tires.

A set of tires?

If all of your tires are wearing out together, you have the greatest flexibility in tire selection. If you were happy with the original tires, simply replace

them. If you want longer treadwear, a smoother ride or more handling, there are probably tires that will help you accomplish that. Review the tire

category types until you find a category description that describes a tire that fits your needs.

How long do tires last? 

How long tires last depends on four things: the design of the tires, the pavement condition of the roads you drive on, how you drive, and how well

you maintain the tires. You have no control over tire design, other than trying to choose a long lived tire based on treadwear ratings and mileage

warranties. You don't have control over the pavement conditions either. However, you do have control of how you drive. The harder you accelerate,

brake, and corner, the quicker the tires will wear. You also control maintenance. Maintenance of tires includes rotation and balance every 5,000

miles to 7,500 miles, maintaining proper tire pressure, and keeping the tires aligned. The better you maintain the tires the longer they last.

Depending on the combination of the above factors, tires can last between 5,000 miles and 70,000 miles.

What's the proper inflation pressure for my tires? 

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This is not an easy question to answer. Everyone has different opinion. I think most experts will agree on the following though.

  Tires shouldnever be run under-inflated. That is, under the PSI recommended in your owner'smanual.

  Tires shouldnever be run over-inflated. That is, over the maximum pressure on the tiresidewall.

  If a tireis wearing on both outer edges it is under-inflated.

  If a tireis wearing in the center it is over-inflated.

Here's our opinion on how to get the proper pressure for your tires. We feel that the owner's manual recommendation is often too low. Why?

Because we have see customers wear the inner and outer edges of a tire with documented history of manufacturers recommended inflation

pressure. We use the following controversial method: fill the tire to an amount under the max PSI listed on the sidewall. For 32 PSI max tires we

recommend filling to 30 psi when cold. For 35 max PSI tires we recommend filling to 32 PSI. For 44 PSI max tires we recommend filling to 36-38

PSI cold. Are these the exact perfect tire pressures for your car? No. Many cars using the exact same tires weigh different amounts and therefore

require different pressures. You can fine tune the pressure for the best tire wear. If you disagree with our method, feel free to use someone else's

or make up your own. Just remember never to inflate under the owner's manual pressure recommendation. If in doubt, it's usually better use a

higher pressure.

Why are tires so expensive? 

Tires are not very expensive when compared with other automotive maintenance costs on a per mile basis. Gas seems fairly cheap if you consider

its price one tank at a time. However, if you keep track of your costs per mile, you'll find that typical total fuel costs for just 10 to 20 thousand

miles of driving actually exceed tire costs. When you are selecting new tires, consider evaluating your situation by comparing "how much per mile"

each tire will cost. Divide the number of miles the tire is likely to last (you can use the warranty mileage for an optimistic number) by the cost of the

tires you are considering. Frequently you will find that tires that are initially inexpensive end up costing more per mile. Not to mention the fact that

cheap tires are more likely to develop defects before the tread has worn down.

Should auto tires have a sell-by date?When Americans purchase food productsfrom grocery store shelves, many of those products have a sell-by date or even a "good before" date that

indicate the lastpossible day a company can legally sell that product or the date when the product will become rotten or spoiled. These dates are used

to protect the consumerfrom food that could possibly harm them if purchased or consumed too late. But what about other products we use, like car 

parts, should they have sell-by dates, too?

If you talk with your mechanic when your car's getting fixed, he'll probably won't mind telling you what area of the car he repaired, the main auto parts

that were replaced and he might even tell you some additional auto part information, like how long a specific component you just bought might last

before it goes bad. Car part longevity isn't a new idea; in fact, car manufacturers affix warranties on new cars and trucks which tell you how long certain

parts are guaranteed for, but one important part of your car often goes unnoticed when it comes to auto part longevity: the tires.

We all know that tires have to be replaced after the tread wears down, but some reports show that tires can actually go bad l ong before this happens.

Tires are built to withstand thousands of pounds of weight and can endure some pretty harsh environments, but over time a tire can lose some of its

strength and cease to function the way it was designed, even if its t read is still deep. Some individuals and safety groups are calling for a little more car 

part information disclosure, like a sell-by date or expiration date for tires, in order to protect consumers.

On the next page, we'll find out why tires may need this expiration date in the fi rst place.

Tire Expiration Dates

Tires, like most other auto parts, are built to withstand a great deal of wear and tear. Unlike other car parts, however, tire manufacturers always give an

estimate for about how long a tire should last. The estimates themselves can range greatly for each tire, but you'll usually see a manufacturer listing of 

how many tens of thousands of miles you may expect out of that particular tire.

When it comes to car part longevity, however, there are alwayscircumstances when the auto part information given by a manufacturer may not apply.

In the case of tires, the estimate of how long a tire can last is based primarily on the tread wear. But some safety advocates want to add an expiration

date of six years onto each tire, regardless of how much t read is left on them. The reason for sett ing up this six-year standard is that some research

has shown that after that amount of time passes, tire failures dramatically increase. The tire industry has not yet set up its own estimate, partly

because it doesn't want to give consumers the idea that its tires are guaranteed to last that long [source: Holguin].

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 Although there isn't a set expiration date as of yet, companies like Ford Motor Company already encourages its customers to scrap their tires if they're

more than six years old [source: Holguin]. But how can you determine the age of a tire?

You can tell how old a tire is by looking on the tire's sidewall. There are lots of markings ranging from the type of tire, a speed rating that corresponds

to a maximum safe speed your tire can sustain, the size of the tire and also when the tire was made; however, if you look after the Department of 

Transportation (DOT) letters, you'll see another list of numbers. If the tire was made before the year 2000, you'll see three numbers after the DOT

letters; the last number indicates the year the tire was made. On newer tires, those manufactured in 2000 or later, you'll see four numbers. The first two

numbers indicate the week it was built and the last two digits specify the year the tire was made. So, for example, if you see a "297" the tire was madein 1997, or if you see a "2409" that would mean that the tire was made in the 24th week of 2009 [source: Holguin].

So now we know how to determine how old a tire is and that some car manufacturers and safety groups encourage a six-year limit on tire age. But how

does a tire's age affect its performance? Read the next page to find out.

How Tires Age

 A tire is comprised of many individual parts that are bonded together through a high-heat-curing process calledvulcanization. As with all auto parts,

normal wear and tear affect a car part's longevity. When a tire endures normal use, several factors contribute to the tire wearing down and losing its

desirable properties. Stress from the weight of the car causes oxygen to be forced against the inside of the tire walls. Heat from a tire's friction against

the pavement can also cause a tire to wear down on the inside. The process of heat and oxygen affecting a tire's material properties is called thermo-

oxidative aging [source: Safety Research and Strategies, Inc.]. 

 According to the National Highway Transportation Safety Administration (NHTSA), a tire ages when there is a "loss in a tire's material properties, which

over time leads to a reduction or performance capabilities" [source: National Highway Traffic Safety Administration]. The NHTSA is conducting more

car part information testing with tires to provide the industry and consumers with the most significant information possible.

If a tire is placed on a car shortly after it's been made, the oxidation that occurs has a minimal effect on the tire because the tread usually wears down

before the oxidation causes any major problems [source: Safety Research and Strategies, Inc.]. But tires that are mounted on a rim, even if they aren't

used or if it's used infrequently, like a spare tire, for example, can still undergo oxidation. Think of it this way; if you buy a gallon of milk but don't open it

for 8 weeks, it doesn't mean that milk will still be fresh when you do use it. The milk will curdle regardless of whether or not you've opened it. The same

goes for tires. Having a tire sitting around for several years may actually reduce its longevity.

Not only does oxygen break down a tire's material properties, but heat also causes tires to break down even faster [source: Gin]. The

NHTSA reported that from 2002 to 2006 a large insurance company said that 77 percent of its tire claims came from five states with hot ambient

temperatures. In addition, 85 percent of those claims were for tires that were more than six years old [source: National Highway Traffic Safety

 Administration].

With tires that are aging before they're even in use, consumers could be purchasing sets of t ires that may not be as long lasting as the mileage they're

guaranteed for. But is this really a problem?

Up next, find out how a tire's age could be dangerous for drivers.

Dangers with Old Tires

From 1994 to 2004, the NHTSA reportedthat about 400 fatalities occurred in the United States due to tire failure [source:National Highway Traffic

Safety Administration]. But a tire's longevity is affected by more factors than just the oxidation issue we talked about on the last page. Other factors that

cause tires to fail can be over- or under-inflation, overloading a vehicle beyond an acceptable weight, improper maintenance, structural defects and

improper installation of the tire [source:National Highway Traffic Safety Administration].

When an accident occurs, auto part information can be entered into a database for statistical purposes, however, the age of the tire is not usually

recorded. So statistics on whether or not older tires are the root cause of tire-related accidents is difficult to nail-down. However, this doesn't mean that

a tire's age doesn't have anything to do with tire failure. The NHTSA reported that a tire can lose its elasticity over time, which increases it's chances of 

becoming dry and brittle on the inside, affecting the car part longevity. When oxidation of a tire occurs, the break down of material properties in that tire

can lead to tread separation [source: National Highway Traffic Safety Administration]. Tread separation is when the tread section of a tire peels off 

from the rest of the tire during use. Oxidation causes the steel belts in the tire to lose their adhesion to the rest of the components. The combination of 

these factors can then cause the entire tread to separate from the tire, potentially causing a driver to lose at least some control over the vehicle.

The NHTSA has received opposition from some organizations, like the Rubber Manufacturers Association (RMA), which is the national trade

association for the rubber products industry. The RMA issued a pressrelease in 2009 stating that, "Allegations that there is a correlation between

tire performance and chronological tire age are unfounded and unsupported by data" [source: Rubber Manufacturers Association]. While other car 

parts and factors may play a role in tire failure, there are many manufacturers including Porsche, Toyota, Ford, Chrysler and BMW who strongly

recommend replacing all tires, including the spare, after six years regardless of use or tread wear [source: National Highway Traffic Safety

 Administration]. The NHTSA is continually studying car part information and the dangers of older tires to provide consumers with more specific data on

this issue.

For more about tires and other auto part information, follow the links on the next page.

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Patches vs. Plugs

We offer two types of tire repair here at Art's Automotive: tire plugs, or an internal patch/plug combo. A plug is about a third of the cost of a

patch/plug, so people often want to know what the difference between the two repairs are before making a decision about which one to choose.

For the record, repairing with a patch plug is the only RMA (Rubber Manufacturers Association) approved way to repair a tire. For more on the

argument in favor of doing things the wrong way, click here. 

A tire patch/plug is the best way to repair a tire, but it costs more because of the additional time and materials necessary to do this type of tire

repair. Here are some of the reasonsyou might want to pay more for this repair:

1. You have expensive tires with lots of tread left, and you want a quality repair to protect your investment.

2. You're willing to pay more increased reliability.

3. A family member drives the car, and while you might go with the cheaper option on your own car, you want the very best for them.

4. Your tire has an injury that can not be repaired with a plug.

If none of these statements describes your situation, click here and allow me to lure you to the dark side. On the other hand, if they struck a chord,

read on.

The first step in any tire repair is to find the injury. This one was easy enough, we just followed the hissing sound to the bit of metal sticking out of 

the tire. We didn't even need the dunk tank.

To install a plug patch, the tire must be removed from the rim. Before that, the wheel weights must be removed to prevent damage to the tire as it

is being removed from the rim.

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Here Leon is "breaking the bead" which basically means getting the tire unstuck from the rim so it can be removed.

Then the wheel is moved onto the turntable and the tire is removed from the rim.

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Here's an inside view of the damage. Looks like it was a large staple that got stuck in this tire so there are 2 holes in it. A plug patch has only one

"plug" portion. This raises the question of whether it would be better to install a separate plug in one hole, and use the patch plug to fill the other,

or to just fill one of the two holes with the patch plug. I think that because the holes are so close together, the latter would be the better option.

We've marked the injury with chalk, removed the staple, and now we're buffing the area.

The buffing removes the slick surface and exposes a "raw" surface the patch will stick to. We also use a solvent to remove the mold release agent

the tire was coated with during manufacture and prep the rubber for the tire cement.

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Next we gently guide a pick through the injury to find the angle and make sure the plug patch will fit through. If it won't, we'll need to use a

carbide burr to enlarge the hole a little. There are different size plug patches for different size injuries.

Tire patch cement is a applied and allowed to dry for 5 minutes or so. Then the plug patch is pushed into place. The plug portion of the plug patch

is encased in a disposable metalsleeve to guide it through the tire.

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Once through the tire, the metal sleeve is removed, leaving the rubber tire plug in place. The rubber plug is then cut so it is flush with the tir e.

The patch is then smushed into the tire using a tool called a tire stitcher.

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Then the whole patch is covered with another coat of tire cement.

Then the tire is installed on the rim, re-balanced, and rechecked for leaks. Even when working at a good pace, it takes about a half hour to

complete the whole process. Plus the cost of the patch, wheel weights, and a valve stem.

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Last Updated on Tuesday, 07 December 2010 16:54

To plug, or not to plug: that is the question: 

Whether it 'tis nobler in the mind to suffer 

The slings and arrows of outraged industry peers,

Or to leave unplug'd the tires I see troubled.

And by opposing them? To save PSI: To end seep. 

Yeah. You're probably right. I should stick to my day job and leave butchering Shakespeare to the pros. The point of this bad bit of poetry was to

illustrate that installing tire plugs is a controversial procedure. Ask 10 mechanics whether it's OK to use a tire plug to repair a nail hole in the tread

of your tire and you are likely to 10 different answers, some of themshouted at you as if you were the stupidest person in the world.

"Yes, I do it all the time"

"No, plugs should never be used"

"Yes, if the nail isn't near the sidewall"

" No, plugs are only for temporary emergency repairs"

"Yes, if you remove the tire from the rim to inspect for damage"

"No, you can only use a plug in conjunction with a patch"

"Yes, if the nail hole is near perpendicular to the tread"

"No, only integral plug patches can be used"

"Yes, as long you can pay cash and don't need a receipt"

"No, we only use patches"

Let me start this article by saying, I'm going to give you the "wrong" answer. How could it not be since mechanic "A" doesn't agree with mechanic

"B" who doesn't agree with tire manufacturer "A" who doesn't agree with tire manufacturer "B" who doesn't agree with the company who makes one

type of patch kit, who doesn't agree with the company makes another type of patch kit, who doesn't agree with the company who makes tire plugs.

No matter what my answer, someone will surely strongly disagree.

The the answer to the question of whether tire plugs are an acceptable repair is certainly more objective than the statement "Blue is a pretty color,"

but less objective than a fact: "Water boils at 212F at sea level." The most credible sources don't like the tire plug as a stand alone repair, especially

if the tire is not removed from the rim for inspection. If you are the type who wants the best quality repair, regardless of cost, I'm convinced that

the integral plug-patches are the *best* repair option. If that's you, well, congratulations on your financial success, and I'd be more than happy to

install a costly plug-patch and help you redistribute some of your wealth (into my pocket). But what about the customer who's struggling to make

ends meet, or would rather spend money on their kid's piano lessons than on the very best tire repair? Should we tell them about how professional

we are and how we don't do nonstandard repairs, and how their tire could loose pressure and crash killing their whole family (failing to mention, of 

course, that they could run over a nail on their way out the driveway after getting an expensive patch repair, and that it's extremely unlikely a tire

leak will result in their death, or any other adverse outcome other than a flat tire)? Should we worry so much about the ever-so-faint possibility of a

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lawsuit that we refuse to do tire plugs for customers, even though every mechanic working here has used tire plugs on their own cars? I'd rather

leave the scare tactics and stonewalling to the professionals out there. We just want to fix cars as a means of supporting ourselves.

Before we knew better, we pulled nails from tires and installed tire plugs from the outside of the tread in, without removing the tire from the rim.

Now that we know better, we do the exact same thing several times per day. Why? Because after many years of installing tire plugs on whole wheel

assemblies, and 99 out of 100 working perfectly, we're pretty confident tire plugs will make a good permanent repair for certain types of 

punctures. At one point my wife's car had 5 tire plugs in its 4 tires, all installed from the outside in, without removing the tire from the rim, and

yes, I do love her, and no, none of the plugs ever failed.

The Rubber Manufacturers Association states that a tire driven low on pressure (as a tire likely might have been if it had a nail hole) can develop

damage to the carcass that can not be detected and could cause rapid air loss (a blowout). But they're not talking about a ti re with a hole, they're

talking about a tire that is just low on air! If we took that statement to the extreme, how would the "professional" mechanic handle a low tire?

Mechanic: "Ms. Smith, we found one of your tires was low on pressure". Ms. Smith: " Oh. Thanks. Did you fill it up?" Mechanic: " Why no, that would

be unprofessional! We replaced it. We wouldn't want invisible carcass damage to cause a blow out!" Silly isn't it? I'm not trying to say the RMA is

wrong. They no doubt know more about tires than I ever will. I just want to temper their recommendations with a little personal experience and

common sense. The RMA also says 88% of the tire repairs they found when examining used tires were "improperly done". We may be doing tire

repairs wrong, but so is the majority of the industry, whether they are aware of it or not.

Let's face it -- sometimes tires go flat! Sometimes it's because a repair didn't work. Sometimes it's because the tire was under-inflated Sometimes

it's because the tire wasoverloaded. Sometimes it's because there was something sharp on the road and you drove over it. Does it really matter

why? If you get a flat, are you going to install the spare and continue on with your commute? Or do you have the fantasy of hiring a company that

does failure analysis and a team of lawyers to avenge your lateness to work and grease smudged shirt? Yeah, that's it. I can see it in my minds

eye.... It's like an episode of CSI, your team of beautiful lawyers will argue the improper repair caused the low pressure that caused the structuralfailure that caused the blowout, against another team of lawyers that will argue the improper repair was holding and the carcass damage from the

low pressure was caused by the driving done with low pressure caused by the original injury before the repair. All this will take place in a

courtroom full of plasma TVs running 3D computer animations in slow motion. Your lawyers will no doubt be better looking and your plasma TVs

will be bigger, so you'll win and receive one zillion dollars and buy your own island. Back to reality. If you want an improper repair with a 99%

success rate, get a plug. If you're the unlucky 100th customer, I'll give your $12 back and you buy yourself a consolation lunch while we fix it again.

Now that I've lured you to the dark side, I should say that there are times a tire plug is a poor repair choice.

If a tire has been driven low on pressure for long enough, it may be damaged, and should not be plugged, patched, or repaired in any way. How do

you tell if the tire was damaged from driving low on pressure? Some sources say to check for rubber powder inside the tire. I f you find it, the tire

needs to be replaced. Obviously you'd have to remove the tire from the rim to do that. Instead, we usually just look at the s idewall for wear where

there ought to be none. If the lettering or sidewall design is worn down, we recommend a new tire instead of repair. We also digitally inspect the

sidewall (fingers, not computers) with the tire deflated, to see if there are any abnormal soft spots. We feel this is all th at needs to be done before

repair.

If the puncture is on the sidewall, we feel it should not be repaired using a patch or plug or both. This is one of those rules repeated by many in the

tire industry. Why do we choose to obey this rule while flouting the "never repair a tire on the rim" rule? We'll, I suppose it intuitively makes sense

that a patch or plug on a continually flexing sidewall will fail.

If the puncture is caused by anything other than a nail or screw, plugging is not a good option.

If the nail or screw did not go in fairly close to perpendicular to the tread, the chances of the plug failing to seal go way up. It's better to patch this

type of injury.

If the tire is a performance tire and the driver pushes it (hopefully on a track rather than around my neighborhood), it's probably better to use a

plug patch or buy a whole tire. Many tire manufacturers say *any* type of repair will void the speed rating on the tire.

If the tire has a hole larger than 1/4", it probably should not be repaired with a plug or any other method.

Other than these exceptions, we're gonna keep on plugging away :)

Last Updated on Tuesday, 07 December 2010 16:55  

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How often should tires be rotated?

Most mechanics recommend tire rotation somewhere between every 5,000 miles and 7,500 mile.

What is tire rotation? 

Tire rotation is simply changing the position of the tires on the car. For example, taking the front tires and putting them on the rear, then takingthe rear tires and putting them on the front. Tires can be rotated in other patterns though. Usually tire manufacturers will publish their preferred

method, which may not be the same as what your vehicle manufacturer recommends, both of which may be different from the rotation pattern your

mechanic wants to use. The truth is it doesn't make a lot of difference which way you rotate the tires, so long as each tire spends equal time on the

front of the car and the rear of the car. Some older and cheaper tires do not do well when rotated side to side, so if in doubt, it's a safe bet to just

rotate front to rear without crossing side to side.

Why should I rotate my tires? 

Tires should be rotated to increase the life of the tire, prevent irregular wear, and to allow all four tires to wear out at the same time so they can be

replaced with a matching set.

Tires in the front of the car develop wear pattern peculiar to the front of the car and tires in rear develop wear patterns peculiar to the rear. Tires in

the front tend to wear on the inside edge. This is caused by scrubbing on the inside of the tire as the suspension compresses when going over

bumps, and by the front wheels' tendency to increase toe-out at freeway speeds. The rear tires tend to develop a choppy wear pattern, which is

caused by the skipping and hopping rear toe-in or toe-out can cause. Rotating the tires helps minimize each of these types of wear by minimizingthe amount of time the tire spends in each position.

Tires that are on the front of a front wheel drive car wear twice as fast as tires on the rear of a car. This happens because -- the engine's power

goes though the front tires on it's way to the ground, the front brakes (and therefore the front tires) do most of the braking, and the front tires

shoulder more of the cornering load. If you left the tires in the same position, the fronts would wear out when the rears were only 1/2 worn. You

would then need to buy two front tires, and you might not be able to match to your rear tires. Since tires have differing handling and traction

characteristics, it's best (but not essential) to have them match.

Should I rotate my spare tire in? 

Most cars these days have a "space-saver" spare -- a spare tire that is smaller than the rest of the tires so it fits neatly in the trunk. Even cars that

have a full size spare often use a tire that is not rated for freeway speeds, or a rim that does not match the other four. Most of the time the spare

should not be rotated in.

What is tire balancing? 

Tire balancing means adding lead weights to a rim to cancel out any heavy areas of the tire. If the tire has a heavy spot, it will cause

a vibration when it spins fast, kind of like a washing machine with an unbalanced load when the spin cycle starts. When the wheel starts to vibrate,

the vibration can be felt in the rest of the car as well. People often report this as the steering wheel shaking, or the rear view mirror shaking, or in

severe cases it has been described as, "like a coin operated vibrating bed in a hotel".

What is the difference between tire balancing and alignment? 

Tire balancing and alignment are often thought to be the same thing, but are actually completely different. Tire balancing means adding lead

weights to a rim to cancel out any heavy areas of the tire. Wheel alignment is adjusting the wheels to point straight ahead (toe), not to lean to either

side (camber), and to maintain stability (caster).

When should I balance my tires? 

We recommend balancing the two tires leaving the rear of the car to go to the front with every rotation. There are two reasons for this: 1) A rear tire

that is out of balance may not cause any noticeable symptom (vibration or shaking on the freeway). However, if the tire is moved to the front during

the rotation, it may cause a very noticeable symptom. And 2) Balancing all four tires with every rotation might be "over serv icing". In other words,

balancing all four tires every 5,000 to 7,500 miles probably would not give you any appreciable benefit over balancing the tires every 10,000 to

15,000 miles, but it would cost twice as much.

Last Updated on Tuesday, 07 December 2010 16:55  

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