Zero pressure, self supporting, run-on-flat…whatever the moniker each tire manufacturer gives to its run-flat tires, the general idea is the same: consumers can continue driving for 50 miles at up to 50 miles per hour on what would ordinarily be a flat tire.
And while cost and ride comfort have long been seen as negative aspects of run-flat tires, today’s models offer technologies that can save consumers money while offering distinct safety advantages, according to tiremakers.
While still making up only a small fraction of the total replacement passenger tire market – no more than a couple of percentage points, according to the companies polled for this article – run-flats are an important inventory item for dealers who service certain vehicle models that are fitted with the tires as original equipment.
According to Robert Saul, UHP and run-flat product manager for Bridgestone Americas, the longest-running and most popular models that feature run-flats as OE include the BMW 3 Series, Mini Cooper and Chevrolet Corvette.
“BMW and Mini hold a commanding share of the OE run-flat market as they have gone almost 100% run-flat for their vehicles, and they hold the crown of the top selling run-flat-equipped vehicle in the U.S. with the 3 Series,” agrees Yokohama’s Kevin Hinton, manager of product planning. “Mercedes is focusing heavily on this technology, as well, and we expect to see a growing share of its vehicles outfitted with run-flats in the future.”
He adds that General Motors’ Cadillac luxury brand is making a comeback with run-flats, and the automaker is looking to equip more of its models with this technology in the coming years, as well. Toyota also features run-flat tires on two of its popular vehicles: the RAV4 CUV and Sienna minivan.
Hinton explains the run-flat market is expected to grow as automakers begin to fit more run-flats on new vehicles. “We expect the growth rate of run-flat-equipped vehicles to outpace the growth rate of vehicles fitted with conventional tires in the coming years,” he adds.
Henry Kopacz, public relations and product marketing specialist for Hankook Tire America Corp., says sales and shipments of run-flat tires have increased from roughly 1.5 million units to 1.9 million units over the past couple of years. He estimates the segment will see an increase of roughly 20% over the next few years.
“W and Y speed rated products have been the most popular for the OEMs and we expect that trend to continue,” Yokohama’s Hinton says. “We also expect growth to occur in V rated tires. Tires in 17- to 19-inch sizes will continue to make up about 90% of all run-flats on new vehicles. Run-flat tires have been a technology that has been fitted mainly on sports and luxury cars, and we expect that trend to continue, as well.”
Run-Flat Pros and Cons
The perceived negatives of run-flat tires are that they don’t perform as well as their non-run-flat counterparts and that their purchase cost is too high, Hankook’s Kopacz explains.
“A great deal of research and design has gone into the latest generation of run-flat tires and consumers have come to appreciate the improved performance of the tires,” he notes.
The ability to drive up to 50 miles at 50 miles per hour after a full pressure loss allows motorists to drive to a service station in order to have their vehicles inspected and serviced – a valuable asset to consumers, Kopacz says.
“Changing a flat tire on the side of a road can be very challenging and stressful,” says Travis Roffler, director of marketing for Continental Tire the Americas. “Run-flat tires can provide convenience and peace of mind for a consumer by essentially eliminating the need for roadside tire changes.”
Aside from peace of mind, run-flats also offer financial positives, according to Yokohama’s Hinton, who says, “For example, if pressure is lost with a conventional tire, wheel damage can occur, which can be very expensive.”
Sales and Service
There are several considerations for tire dealers to keep in mind regarding run-flat tires, including TPMS, vehicle manufacturer guidelines and proper recommendations for customers.
Bridgestone’s Saul says tire dealers must ensure the vehicle has a functioning TPMS and that the tire is free of damage that would compromise its run-flat function. “Pay attention to the TPMS and heed any warning with prompt attention to tire pressure,” he notes. “In the event the tire is losing air, driving should be minimized and drivers should get the tire inspected as soon as possible.”
“TPMS is necessary since it is difficult for a driver to notice when a run-flat tire is without air pressure,” advises Continental’s Roffler, who added, “Continental self supporting run-flat (SSR) tires may only be fitted on vehicles for which they are approved by the vehicle manufacturer and that are equipped with TPMS.”
He also notes that run-flat tires should not be mixed with standard tires on the same car – even when paired on the same axle.
Puncture repair also should be considered, according to Yokohama’s Hinton, who says, “Yokohama Zero Pressure System tires are not to be repaired following a puncture or any other tire disablement. They are covered under our standard limited warranty, which provides a replacement tire on a prorated basis based on the remaining tread depth when a tire has been damaged due to a tread area puncture within the repairable area and limits defined by the RMA.”
In terms of offering advice to run-flat customers, dealers should remind drivers to use “extreme caution when driving at zero pressure” and to “avoid aggressive handling actions and any unusual service condition, such as trailer towing or hauling heavy loads,” Hinton adds.
Dealers also should stress the need to follow vehicle and tire manufacturer instructions on maximum speed and distance for driving on a run-flat tire without air pressure. “When the TPMS detects low air pressure, avoid extreme driving conditions such as sudden or erratic braking, acceleration, steering maneuvers, etc., and have them visit a tire dealer as soon as possible to have the air pressure checked,” Hinton says.
Stocking considerations vary between different markets, so through its Gold program, Continental works with dealers to analyze local markets and helps them determine which products and sizes to stock, Roffler adds.
Yokohama’s Hinton estimates a dealer could stock 20 run-flat sizes and cover about 70% of the U.S. run-flat market.
Fewer SKUs reflect the small percentage of the overall replacement tire market that is comprised of run-flats. But in order to service many luxury vehicles – and an increasing amount of mainstream models as automakers add more OE run-flat fitments – tire dealers need to keep up on the trends and service recommendations of this segment.
