Oversize tires


#1

Many new cars that offer 17" to 19" tires warn that they may last only 15,000 miles. Why would they last so much less than say a 15" tire?



Louie


#2

Please elaborate. The largest tires I have are 16 inch and they already have 30K on them with a lot of wear left. I have not heard this. I do know that the early run-flat tires got about 15K if they were lucky. They were the worst tires I ever had and I paid a premium for them.


#3

I assume you’re referring to low-profile tires. Here’s my guess. Low-profile tires are meant for people who value performance over other qualities. In order to get good traction, you need softer rubber, which of course will wear out more quickly.


#4

It’s not the size that makes them wear out faster, it’s the tread compound. Tires in the larger sizes are usually “high performance” tires with V or Z speed ratings. Tires of this type don’t last very long, regardless of their size.

Some ultra-high-performance tires only last a few thousand miles.


#5

I agree; you’re confusion tire size with rim size. The overall diameter should be the same for each with the larger rim size reflecting a lower profile tire. All things being equal, you could argue that 17 to 19" wheel tires should last longer because of less sidewall flex and better handling. But all things are not created equal and it has more to do with the engineering of performance tires in general with different rubber compounds which are normally found in lower profile tires…Shop around and you can get longer mileage, lower profile tires that may give up a little on cornering for example.


#6

Like the others said, it’s the high-performance rubber compound used. Which is OK if that’s what you want, but these low profile tires are showing up on lots of non-high-performance cars. Article a year ago about a frustrated Avalon owner who found out his had these short-lived tires.


#7

If they’re the stock tires, it’s no wonder. The manufacturer buys the cheapest tires for their vehicles to save money for each unit made. Even $5 adds up over many vehicles. go to Tirerack.com and look at some of the O.E. tires for any vehicle, you’ll see that most tires are not only cheap, but also offer poor traction in most conditions(I’m looking at YOU Subaru)


#8

When you move towards “performance” and/or “visual impact”, tread life becomes secondary. In the real world, many of these super-low-profile tire/wheel combination’s fail long before wear-out occurs…They are VERY susceptible to pot-hole damage and bruise-breaks and the ride quality noticeably suffers because of the very narrow side-walls…


#9

Yup. As almost everyone has told you, those larger tires are almost surely ultra low-profile, “performance” rated tires. They will provide improved handling, albeit at the cost of a much harsher ride, much shorter tread life, and–all too often–damage to those very expensive alloy wheels.

If driving like a “boy-racer” on local streets is a priority, or if looking like a pimp or an urban purveyor of controlled dangerous substances is someone’s goal, then these tires are a great idea. On the other hand, for those of who do not aspire to that type of image, they are a very bad deal.


#10

As already stated, it isn’t the rim size (17", 18", 19" or whatever) that puts them in a catagory of shoort lived tread, it’s the rubber compound. That can to a certain extent be ascertained by the speed rating. Unfortunately, as McP pointed out, many low-profile tires only come with high speed ratings, thus softer compounds and shorter life.

The “upside” is that the provide improved handling, as VDC pointed out.

My car came stock with 215x45/17Z tires. That means they’re 215mm wide at their widest point, with an “aspect ratio” (sidewall to width) relationship of 45%, and fit 17" rims. While one manufacturer does make them in an “S” speed rating (up to 112 mph sustained), most manufacturers only make them in “V” and “Z” speed ratings. I’ve chosen not to compromise the handling by ordering the “S” rated tires, but I pay a price. The most I can get out of a set is about 30,000 miles max.

I suspect that the reasons so many cars come stock with these high performance tires is style, style and style. But I have to wonder if lower rotating mass and the extra .1 mpg it might provide (wild guess) is a factor in the decision.

www.carbibles.com has a good primer on tires. I recommend a visit.


#11

I’ve tried to reason the movement to larger rim sizes when 15" was used for many decades. I can only figure that it’s a consumption/consumer thing. While I’m sure there are fractional reasons for the larger rim/smaller tire in terms of handling and sidewall flex, I think it’s more of an employment/obsolescence evolution. Retooling in wheels …retooling in tires …no discounted 17" tires …etc…etc. OEM contracts …aftermarket contracts …patented fluids …changes in body styles …proprietary fixtures …parts …etc…etc.

That sorta thing has been the invisible elephant in the auto market forever.

How much do most geezers (I’m one) need to pull .00007 more G’s on the skip pad??? Enough to cost BILLIONS in the total consumer market? I think not. Advancement for a good cause is a good thing. Advancement because engineers need to pull something out of their behinds to keep a job? That’s another.


#12

Still-employed engineers everywhere would disagree.

Unempolyed engineers everywhere wish they’d been able to pull something out of their behinds that would have kept their jobs.


#13

[b]Still-employed engineers everywhere would disagree.

Unempolyed engineers everywhere wish they’d been able to pull something out of their behinds that would have kept their jobs. [/b]

Yes …they would. There is such a thing as diminishing rate of return. Now we do admire the Teutonic’s who appear to employ engineers that sit around all day thinking of nothing but complicating the wheel, but I admire it from afar. They do it very well and don’t appear to care how much it costs or how obsolete that they make their last greatest creation with their next one. They don’t care what the lubrication or tire industry has to do to enable them at their task.

…but there’s a collision between innovation and productive gain. We’ve reached it long ago. One good example is Dex VI fluid. Sure it’s superior to its predecessor…but SO WHAT? Was there really a deficiency before its creation? What it did was create a cash stream to GM through the back door with licensing. You’ll see more and more of this as manufacturers seek to gain revenue in light of reduced new car sales.

New spec’d fluids …new forms of tribute paid to the OEM to produce them. Repeat as needed.

Why does my AX15 require synthetic GL3 (not available in North America under ANY blender) fluid? Why are my soft metals so sensitive NOW (and back a decade or more) when manual gear boxes, for many decades, survived well enough on 90wth hypoid??


#14

It’s called progress.

Although in the case of ABS, LCD displays, sequential “menu driven” basic controls, and BMW’s I-Drive perhaps it’s really regress. But I digress.

So many gresses, so little time.


#15

Thanks for all the info guys. So when my Lexus IS 350 comes standard with 225/45VR17 all season tires with the warning that “tire life may be substantially less than 20,000 miles”, I just wait until they wear out and replace them with harder rubber S rated tires? Sounds like it.

Louie


#16

All of which, while providing added utility tend to cost more than that which they provide. The failure of such systems is what retires many an otherwise functional chassis.

Then again, some people really appear to enjoy a $500/month new car rental. They only think that they’re buying it.


#17

Kinda defeats the purpose of buying a sports sedan in the first place doesn’t it? Also, some (but not all) tire places won’t install tires with a lesser-than-stock speed rating. They make V rated tires that last for 40k miles these days anyway.


#18

FoDaddy is correct. I doubt if any shop would put an S rate dtire on that car. The IS 350 is capable of maintaining over 112 mph, and there’d be a potential liability issue.

I’d stick with the V ratings. I’m on my second set of Hankook all-season 215/45VR17’s right now and I’ve been pleased with the ride, the handling, the wear, the wet weather traction, the performance in snow, and the cost. There are surely other good choices, and certainly more expensive choices, but that’s just my personal experience. I had Coopers on before and while the winter traction was the best I’ve ever owned the life of the tires was terrible and the ride only acceptable. By the way, I routinely push the car well beyond 90 when passing, sometimes pushing 100, and the Hankooks are smooth as a buttered bottom with excellent handling at those speeds. Um, I’m not recommending those speeds, you understand…I’m just sayin’…