Saturday, November 12, 2011

Why New Car Tires Wear Out So Fast


The tires that came with your last new car were not designed by Michelin, Goodyear, Bridgestone or any other tire manufacturer. They were designed by the manufacturer of your car. If your new car came with a set of Michelins, Michelin made the tire but they made it to the specifications set by your car manufacturer. These tires are referred to as OEM (original equipment manufacturer).

Furthermore, your manufacturer does not warranty the tires on your new car even though he tells you that you have a “bumper to bumper” warranty. The last time I checked, my tires were between my front and rear bumpers. Even though GM designed the tires on your Chevrolet, they have no responsibility if they are defective. The tire manufacturer bears that responsibility.

The OEM tires that came with your car can’t be replaced (which is a good thing) after they’ve worn out. And they will wear out much sooner than they should. This is because virtually all auto manufacturers specify very soft rubber which means they wear out too fast. Why would the manufacturer do that? They want that new car to have the smoothest ride possible, even at your expense of having to buy a new set of tires at half the mileage you should have to. When you test drive that brand new car and it rides very, very smoothly you’re more likely to buy it. You’ll find out how fast the tires wear out much later, and when you do you’ll blame it on the tire maker.

By the way, another way the car makers delude you into thinking your ride is very smooth is by recommending low tire inflation. The number you see on your door jamb or in your car’s owner’s manual is the car manufacturer’s recommended air pressure. The number on your tire is the tire maker’s recommendation. The number on the door jamb is the minimum and the number on the tire is the maximum. There’s typically a 10 pound difference.  I recommend you try the maximum and, if the ride’s too rough, split the difference. You’ll not only get longer tire wear but better gas mileage.

I can’t prove it, but I suspect another reason auto manufacturers design their own tires is to cut costs. By cutting a few corners in the design and specifications, they can increase their profit and/or cut the overall car price. If there purpose was to design a better tire, why wouldn’t they make these OEM tires available for the car owner to buy after the first set wears out? Many car owners “think” they’re replacing their Firestones or Michelins that were on their new car with the same tire, but they’re not. The tire might be the same size and look the same, but it’s a different model number.

One thing you should look for on your first set of replacement tires is the “tread wear index” which is molded into the side of your tires. This number will be 200 to 800. Your OEM tires will have a lower number because their made of softer rubber. If the tires that came on your car had a 200 tread wear index and you replaced them with 400, you should get twice the mileage on your second set of tires. The car might not ride as smoothly, but most people can’t even notice. And to my way of thinking, cutting you tires cost in half is pretty good compensation for a slightly rougher ride.

When replacing your tires, don’t get enamored by a sexy brand name. Brands aren’t always built on quality but also on advertising. Also, a famous brand tire makes all different kinds of tires to many different designs and specifications. Just because it’s a “Michelin” doesn’t necessarily man it’s a good tire. If Michelin made that tire for an auto manufacturer who designed the tire with only two things in mind…low cost and soft ride, you didn’t get a very good tire. My recommendation is to check Consumer Reports for the best tire replacements. You’ll find tire brands recommended that you may never have heard about. The Japanese and Chinese make some very good tires but they have funny sounding names and you don’t see them advertised heavily on TV. 

11 comments:

  1. Thanks, Russ.

    Unfortunately most new car buyers don't undertand that the tires that come with their brand new car probably will wear out sonner than they expect.

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  2. I wonder if some of that early wear might be the result of not rotating the OEM tires like we ought to. I know that's my problem; I just forget. When I get the first replacement set, though, my dealer's gonna ask, "You want lifetime rotation?" and I'm gonna say, yeah, that's probably a good idea. Then every time I get my oil changed, they'll rotate the tires.

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  3. Thanks for your posting on not rotating your tires.

    No, that's not the reason OEM tires wear out faster. They wear out faster because the manufacturers specify softer rubber (lower tread wear index) than they should.

    Not rotating your tires won't lessen the amount of wear. It will only cause them to wear unevenly. You definitely should rotate your tires every 5,000 miles.

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  4. Tires can be too technical at times. There are a lot of specifications that a normal car owner might not want to dig into. However, the longevity of a tire depends largely on the owners. One way to prolong your tire’s life span is to avoid overloading. Also, make sure that it always has the right amount of pressure every time you drive.

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  5. Thanks for your posting, Rita.

    I totally agree with you especially about proper air pressure. It should be checked at least monthly and should be between the recommended pressure of the car manufacturer, stamped on the door jamb and the tire manufacturer stamped on the tire.

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  6. I guess it all boils down to preference: whether a car owner wants a smoother ride but shorter lifespan for his tires, or a slightly rougher ride but longer service life for his tires. Still, it’s good to know these pointers so car owners out there can make an informed decision. Regarding the considerations Rita mentioned, and to add to the tread wear index that you mentioned, one must also consider his car type, car handling, and the usual terrain that he drives on when choosing a set of tires.

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  7. I am a snow bird from Wisconsin and load up my Sienna to the max and head south for the winter. It eats up my tires like crazy.
    The answer is to get a truck.

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  8. can i make the car dealer to exchange their tires for tires for tires that have a longer thread life when i purchase one of their cars

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  9. I think it's worth a try asking the dealer to switch your OEM tires with tires having a higher treadwear index, TWI. They're under no obligation to do this, but if you make it a "condition of buying the car" from them I believe you have a good chance of succeeding.

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  10. I completely disagree with your recommendation to ignore the car company's tire pressure recommendation and try to test using the maximum pressure on the tire sidewall.

    I have tested and monitored tire wear and found that if you do that, you will prematurely wear out the center treads.

    You should follow Mercedes Benz' honest sounding advice. Use their figures if you want a smooth ride and add 3 more psi if you want better handling and gas mileage. They don't say to dramatically overinflate, just 3 psi more.

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