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New Tires

I bought a 2001 Toyota Corolla in the Fall of 2007. I’m not sure the last time the tires were replaced. How do I know when its time to replace them?

How many miles are on the car? The original tires lasted somewhere around 30 to 35K miles. You should be on a 2nd or 3rd set of tires at this point depending on miles driven.

Inspect all 4 tires the tread should be worn evenly from the inside to the outside of the tires. Do all 4 have about the same amount of tread depth? If yes, then when it is time to replace you’ll need 4 tires. If 2 are worn more than the others you may need to replace 2 sooner and the other 2 later.

The “penny test” is to put the head of a penny into a groove in the tread of the tire. If you can all of the hair on Lincoln’s head your tire is worn out. The “tread bar test” is to find a tread bar on the tread, they are spaced about every 12 inches across the tread of the tire. When the tread is worn down to the tread bars across the width of the tire; the tire is worn out.

Many people replace their tires before they wear out completely. When the tread flunks the tests above the tire is unsafe. It will lift off the roads surface easily when it rains, this is called hydroplaneing. Flunking these tests also means your tires will not pass inspection in many states.

Most tires have wear indicators molded into the tread. You can see these little “bars” in the circumferential grooves of the tires.

When the rest of the tread wears down to match the “bars,” it’s time for new tires.

If you are worried about how old your tires are, there are codes stamped on the sidewall that are pretty obviously something like a serial number in a long oval area. The last 4 numbers are a code for the week and year of manufacture of the tire - so if you find 2304 then it is a tire made in the 23rd week of 2004.

Well just to be inclusive, tyres should be replaced when the tread is low (penny or bar test) Uneven wear, damage, or (often ignored) age. After about three years, you should consider replacing tyres if the car is parked outside in a sunny par of the world. If you par in a garage much of the time, you can up that a year or two.

I strongly recommend replacing two at a time and ALWAYS put the best two on the back axel. Yea the back.

This is an indication that the OP has not bothered to read the Owner’s Manual!

Just as the manual deals with virtually every other topic related to the safe and economical operation of the vehicle, this little book definitely has a graphic that shows the “wear indicators” that are molded into the tread of all modern tires. Once those wear indicators are level with the remaining tread, it is definitely time to replace the tires.

Personally, I do not wait for the tread to be worn down to the wear indicators, simply because wet weather traction decreases dramatically as the tread wears down and hydroplaning increases greatly. Since it is impossible to put a price on safety, I opt to replace my tires before the wear indicators have a chance to do their job. In addition to the safety factor, road noise from tires also tends to increase dramatically as the tread wears, so a worn tire tread is also a “quality of life issue” as far as I am concerned.

And, as was implied in some of the other posts, the age of the tires is a factor, even if the tread is still in decent condition. If the age of the tires (as shown by the codes stamped into the sidewall) is more than…let’s say…6 years, the tires need to be replaced, regardless of how much tread remains.

(To return to the issue of the apparently ignored Owner’s Manual, if this is one of those used cars that had its manual looted prior to purchase, then the OP needs to buy a manual, perhaps from e-bay.)

The penny test really puts you at the end of the tire’s life & safety. I’ve started using a quarter instead. That gives a much better margin of safety.

Check this tirerack article out>>>>> http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=51

Very easy to understand and explains various depths and what it means.

Here is the kicker. If you encounter winter conditions such as snow/ice on a regular basis toss the tires if at or below 4/32" given winter is approaching.

Nice link.

I really can’t add anything to the already great posts except to also emphasize that tires are one of the most critical safety items on the vehicle. They’re the single only things connecting the car to the road, and they’re doing so on four patches of rubber about the size of the palm of your hand. They’re also the thing most dramatically affected by road conditions. Tires that are nearing the wear bars are no longer safe on poor road conditions. Handling and brakeing can be dramatically deteriorated on worn tires.

I drive about 30-35,000 miles a year. I never allow myself to approach the winter season without new rubber, even though I could probably get another 5-10,000 out of the tires. It cost me $525 dollars this year. That’s dirt cheap to prevent a crash, which I’d surely get into if I pushed my luck. If I’m wasting about 1/3 of the tire, then I’m only throwing away $175 bucks worth of unused rubber.

If you’re in doubt, replace the tires. It’s worth a few hundred lousy bucks. I’ve wasted that much on infantile whims.