Buying tires (make me a sticky)

[mattwithcats]

Buying tires is easy, yet hard because there is so much to remember...

First thing you want to do is look at your car. Make sure all four existing tires are the same size, and that the door sticker matches. The door sticker may not match if the rims have been changed, or the tire size changed.

Optional...
Now figure out which one is the best, and save it for an emergency spare. Rims are cheap, and you can store this in your garage. Gets you through a blowout and gives you time to shop around for a replacement.

Now find the worst. Look for possible worn out suspension components if really bad. If only buying two, pick the two worst for turn in.

Consider up-sizing. I had 185/65/15's on my SL2, first time I bought tires, I put 205/60/15's on (first number up 10, second number down 5 as a general rule, I wanted bigger so I went up 20 for first, and down only 5)

http://www.miata.net/garage/tirecalc.html

Look for a M/S on the new tire, this indicates an all season.

Look for an A traction, A temperature on the sidewall of the new tire. "B" temp is OK, but not the best, "C" is gov't minimum...

Multiply the treadwear by 200 to get estimated miles. They will wear faster on the front of a front wheel drive car.

Divide the price by the treadwear to get cost per mile, lower number is better.

Now break the date code. Since 2000, the week and year the tire was produced has been provided by the last four digits of the Tire Identification Number with the 2 digits being used to identify the week immediately preceding the 2 digits used to identify the year. Tires should be 9 months old or less, and not greater than 18 months.

New
Watch out for "Eco" or "Low Rolling Resistance" tires. they can wear faster, and have less traction. They can also look nearly exactly like their "regular" brother / sister tires.

Name brand are nice, but a blemished or generic with the right markings can be had for half or less of the name brand.

Any other questions?

 

[randomhero439]

Some good info. But to get an estimate of mileage based on Treadwear Rating, multiply the treadwear number by 72.

Also, Eco or LRR tires usually last alot longer

On a side note, summer tires have better hydroplane resistance than an all-season. At least when temps are above 40*

 

[davebarnum]

"Buying tires" a sticky on an oil site? Um...

 

[MrQuackers]

Welcome to the jungle.

 

[volk06]

Up sizing tires on a car can be challenging. Most shops only put on what the car is spec'd for and if something bad happens with the wrong size tire things can go out south fast.

 

[Artem]

What about heat cycling the rubber? Tire rack suggests that it extends tire life and performance.

 

[TMoto]

I've understood that the treadwear number is only useful when comparing among the same brand. For example, a 200 treadwear rating on a Brand A tire may not necessarily give the same mileage for a 200 treadwear rating from a Brand B tire. Is this not true?

 

[bvance554]

Originally Posted By: davebarnum
"Buying tires" a sticky on an oil site? Um...


Or making a post... any post and suggesting it be a sticky? Um...

 

[bvance554]

Plus it sounds like a lot of drunken gibberish tire non-sense.

 

[CapriRacer]

Originally Posted By: TMoto
I've understood that the treadwear number is only useful when comparing among the same brand. For example, a 200 treadwear rating on a Brand A tire may not necessarily give the same mileage for a 200 treadwear rating from a Brand B tire. Is this not true?


First, there is a standardized test that is supposed to be run against a control tire to get a treadwear rating. Put a different way, UTQG treadwear ratings ARE comparable between brands.

- BUT -

A tire manufacturer is under no obligation to publish the actual rating the tires got on the test. He just can't exaggerate the value. In other words, he can publish values lower in the results, but not higher.

The marketing departments of each tire manufacturer has a large input into what is published. Some are very aggressive, and some are conservative. But they all want their tire line-ups to make sense.

Plus the test is highly variable. It can be run many times with different results. To be clear, good wearing tires will always get good values and fast wearing tires will always get low values, but the value obtained varies - my guess about 10%.

So there you have it. You have to take the rating will a grain of salt, but you can compare between brands, but I think anything within 10% doesn't indicate much difference.

 

[threeputtpar]

Barry, so what you're saying is that the test doesn't produce repeatable results and even if it does the marketing department can under report those results? That's hilarious!

What's the point of the test then, from a consumer's viewpoint? Rhetorical question.

 

[CapriRacer]

Originally Posted By: threeputtpar
Barry, so what you're saying is that the test doesn't produce repeatable results and even if it does the marketing department can under report those results? That's hilarious!

What's the point of the test then, from a consumer's viewpoint? Rhetorical question.


I wouldn't say "not repeatable". I would say variable. As I said in my previous post, good wearing tires will get high values and poor wearing tires will get low values.

What's the point of the test? Well, that was what the tire manufacturers were saying BEFORE the test was mandated - and they have been saying it since.

HOWEVER, it is a tool and it can be used if the tool is understood.

If you are comparing 2 tires and the UTQG treadwear rating is within 10%, then it is possible that the real difference is small enough to ignore.

More importantly, tires with high UTQG treadwear ratings are NOT going to give good fuel economy - and some people think that is important.

Not a rhetorical question at all.

 

[SubLGT]

Originally Posted By: CapriRacer
............. Put a different way, UTQG treadwear ratings ARE comparable between brands..........


Tire Rack sees it this way: ".............Typically, comparing the Treadwear Grades of tire lines within a single brand is somewhat helpful, while attempting to compare the grades between different brands is not as helpful..........."

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=48

 

[GC4lunch]

Originally Posted By: mattwithcats

Look for a M/S on the new tire, this indicates an all season.

There are many inaccuracies and bad advice in the post, but I'll addres only the one above.

M/S is a definition carried over from the 1950's that refers only to the geometry of the tread pattern. Primarily, it refers to the block to void ratio, and designates a tire that will look like a traditional snow tire with wide grooves and "lugs" at the edge of the tread. M/S tires tend to be noisy and harsh riding.

M/S with a mountain snowflake logo is a certification mark (the "M/S" may be omitted: the certification mark is the mountain snowflake) that is meaningful in respect of snow traction. If you are going to be doing significant driving in snow, you would do well to get a tire with the mountain snowflake logo on it.

All-season is an informal term; there are no standards to which a tire must comply to be called "all season." The great majority of all season tires do not conform to the geometric standards of the M/S designation. You could designate a banana all season if you wanted to. As a matter of custom, the industry uses all season to designate tires in which the tread compound has been modified so that it does not readily shed water. (It is called a "hydrophilic" compound.) Under pressure, from the mass of the car, snow under the tread melts at the micro level, them recrystallizes, just as it does when you pack a snowball in your hands. You cannot throw loose snow, but you can throw a packed snowball; similarly, the tire with a hydrophilic tread can gain traction on snow where a tire that sheds water cannot.

The trade-off for gained snow traction is significantly degraded rain traction. For a tire designer, snow and rain present directly conflicting conditions. The tire designed for wet roads should evacuate as much water from the tread area as possible. You want the tire to contact the pavement directly, not ride on a film of water. All season tires, because they retain water on the tread, typically require much longer distances to come to an emergency stop from highway speeds on wet roads, and may suffer less control during the deceleration. Antilock braking systems (ABS), by rapidly releasing the brakes when the wheels lock, will help retain control, but add to the stopping distance. If a significant part of your driving is under rainy conditions and you rarely drive in snow, you would do well to avoid "all season" tires.

 

[surfstar]

Originally Posted By: bvance554
Originally Posted By: davebarnum
"Buying tires" a sticky on an oil site? Um...


Or making a post... any post and suggesting it be a sticky? Um...


Not just a post - a FIRST post!


Bravo Sir - you have the self-esteem of someone with large balls. Maybe that's where the stickiness is, as I don't see anything worth sticking in the OP.

 

[Dominic]

I think this is more helpful, as a lot of what is stated above is true but some of it is false.
http://www.tirerack.com/about/techcenter.jsp

specifically this is the most helpful for new consumers
http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=48