Ask Joe Mechanic: Flat Tires

Most of us have had to deal with a flat tire at sometime in our years of driving. They usually occur at the most inopportune time, such as when you are all dressed up or you are on your
way to work. Others happen when it is raining or snowing or it is blazing hot or freezing cold. Imagine never having to deal with a flat tire again! Sounds too good to be true, but it is. You will be happy to know that run-flat tires have made their way to the market and are now available for many vehicles and are standard equipment on some.

Although run-flat tires have been around since 1994, they have only recently become available for many vehicles. There are two basic types; self-supporting tires (SST) and
patented auxiliary support tires (PAX).  Both are designed to support the weight of a vehicle for 100 miles, some more, and allow drivers to continue down the road safely until they can get to a shop to have repairs made. SSTs rely on heavily reinforced sidewalls to support the vehicle’s weight, while PAXs rely on semi-rigid support rings.

Run-flat tires do offer many advantages, most important of all being the convenience of not having to worry about changing a flat tire. You can leave that to the repair shop. They also open up the space that housed the spare tire, jack and lug wrench to be used for other things. Vehicles with run-flat tires have tire pressure monitoring systems to warn the driver of a deflating tire. This reduces the risk of a blowout, but it also lets you know if the tire is a few pounds low and needs a little air, which will help you save gas. In case a blowout would
occur, these tires handle the sudden deflation much better and will help you retain control of your vehicle.

Because this technology is still fairly new, there are still some problems.  Run-flat tires are heavier, yes there is some weight saved by no spare and tools, but not as much as the weight difference over regular tires. Some people who have had run-flat tires report that they do not wear nearly as long as conventional tires. They also cost more and are not available at all tire shops. In many cases they can be repaired, but you must find a shop
with the expertise and equipment required to service them.

As run-flats become more commonplace, many of these problems will undoubtedly be worked out. In the meantime, consumers may want to weigh the pros and cons ofrun-flats before purchasing a vehicle equipped with them. Definitely, before you make that purchase, get as much information about the tires and their cost and reliability.

Recent recalls

802,769 Toyota Avalon, Venza, Camry, and Camry and Avalon Hybrids, 2012-2013,
Air conditioning drain can block causing water to back
up and leak into the air bag module,
possibly causing it to short out. This
could cause the air bag to either
inadvertently deploy, or else fail to
operate at all.

29,000+ Harley-Davidson, 25,185 touring motorcycles and 3,861 Custom Vehicle Operations and Trikes built between May 3 and Oct. 14, 2013 (2014 models).
Some of these motorcycles may exhibit a condition in
which the hydraulic clutch system may
lose the ability to generate enough lift
to disengage the clutch.

If you think you are affected by any of these recalls, contact your dealer or the manufacturer for further instructions.