Going Single in a Dual World - Tire Review Magazine

Going Single in a Dual World

Going Single in a Dual World

By now you have likely heard about the new single wide-base tires – super wides,

as we call them – being offered for line haul applications by several of the major truck tire manufacturers. Michelin, Goodyear, Bridgestone/Firestone and Continental all have their versions, and all are in various states of development or marketing.

Before jumping to any conclusions or recalling experiences with earlier generations of wide-base tires, there are some important things you should know.

The earlier wide-base tires were originally designed for high load and extra flotation applications on vehicles that operated in mixed-service – or combination on/off road ®“ environments. Heavily loaded steer axles of ready-mix concrete trucks, waste haulers, brick/block delivery trucks and mobile cranes are examples.

These vehicles generally operated at limited speeds in local delivery duties. Three sizes have been popular, 15R22.5, 16.5R22.5, and 18R22.5.

These tires date back to at least the early-1960s and were originally bias ply designs that have since been converted to radials. They were renamed to more current metric size nomenclature (385/65R22.5, 425/65R22.5, and 445/65R22.5, respectively) during the mid-1980s/early-1990s time period. They are evolutions of, and share many design features and material types with, their more conventional 75 to 90 aspect ratio counterparts typically used in dual tire pairings on drive and trailer axles.

Over the years, some innovative truckers have fitted these single tires in place of duals on drive and trail axles with varying degrees of success and difficulty. Certain bulk haulers and local fleets have been the most vocal advocates. Weight savings (lighter tare weight), and reports of improved fuel efficiency vs. duals have been the most commonly cited attributes.

On the other hand, driver acceptance, sustained high-speed durability, replacement tire availability for over-the-road in-route failures, lack of limp-in capability, and axle width/wheel offset dimensions have been common issues.

In short, these earlier generation wide singles showed significant promise in line haul service, but were limited by their heritage of vocational designs, a spotty supporting infrastructure, and axle-end hardware originally tailored for dual tire fitments.

Evolution by Design

Fast forward to the current crop of line haul tire offerings.

Tire manufacturers have continued to achieve evolutionary, yet significant, advances in truck tire tread life, casing durability, fuel efficiency, and retreading technology during the past decade.

But in the last several years, bus and truck manufacturers, primarily in Europe, have begun asking for new single tire technology that could take vehicle space utilization, ride and handling, and operating efficiency to new levels. More space means more cargo, more comfort and more income.

Some vehicle designs have been specifically modified to allow single tire fitment – wheelhouse enclosures, cargo storage areas, axle and suspension components, While that may preclude retrofitting to duals, cost advantage was the driving factor.

There is also an increasing emphasis on improving ride comfort and dynamic handling characteristics of many new global truck and bus platforms. Again, super wides are under consideration there.

Tiremakers have been working on these challenges, developing a somewhat fresh approach with super wides. But this work has not been without its own set of challenges, mostly in existing production (how do you make them?) and tire technology (how do you move past current 75- and 80-series line haul type tires?).

For example, the wider tread of the new generation single tires needs to be shaped and restrained more positively in the crown area than allowed by current belt packages. One answer applied by a manufacturer is the winding of a single strand of steel cord circumferentially and across the tire face.

Also consider that with half as many sidewalls and beads on a super wide vs. conventional duals, more of the lateral forces controlling cornering and handling will be transferred to the wheel. However, this reduced number of flexing sidewalls can also be expected to result in lower tire rolling resistance and improved fuel economy in over-the-road service.

Another consideration is that positioning the outer tire sidewall of the super wide single tire as far outboard as the current dual tire requires the use of significant wheel offset, a source of concern to several of the major axle, hub and bearing suppliers. Reducing the overall track width may raise driver issues of perceived stability problems, and complaints of not being able to see the tires in mirrors as readily when checking clearance for cornering, backing or periodic visual inspections. Some industry sources suggest the best solution may be wider axles than are currently used with the dual tire sets.

Advantages Aplenty

Despite some of the challenging issues, several industry trends and concerns could be positively impacted by a growing acceptance of super wide single tires in place of duals. First, it is now documented by studies that the majority of roadside tire debris results from underinflation. This knowledge, considered together with an emphasis on reducing maintenance requirements, costs, and tare weight, favors the use of tire systems that eliminate eight of the 18 wheel positions on the rigs of today.

Even if inflation maintenance systems were fitted to these vehicles, the complexity and costs would be reduced with fewer tire valves requiring hookups.

Labor saving may be possible if larger inflation valves, such as those used on earthmover-type tires, are adopted with the new single tires. This would reduce the time required for inflation when mounting, and may even improve tire/wheel assembly uniformity due to the more rapid bead seating.

One intriguing question that remains to be addressed is the fate of steer axle tires of current 75- to 90-series design once their initial tread life has been realized.

The Road Ahead

There appear to be some very promising advances possible with the new super wide single-tire concept and other recently announced developments. There is no doubt this growing technology could dramatically change the appearance and performance of the 18 wheelers we know today.

It would seem to be an excellent opportunity for vehicle and tire manufacturers and component suppliers to work together to develop complementary parts and engineering designs that will allow the full benefits to be derived from this technology.

You May Also Like

Training and Technology Will Lead the Way in OTR Tires

When we look at how OTR tires keep up with innovations in equipment, it’s all about maximizing productivity.

Yokohama-construction-tires-OTR

After two years of probably the strangest logistics we've lived through—and a roller coaster ride of an economy—the OTR tire market is surprisingly robust. The construction industry has slowed down slightly, and there's a lot of talk about a recession, but so far, we haven't seen a lot of publicly or privately funded projects pull back, and quarries and mines are running hard. All that activity is good for the tire industry.

Last-Mile Delivery Tires Set to Outpace Long-Haul Tire Volumes

Prior to the pandemic, the last-mile delivery (LMD) market was booming. So, when COVID-19 hit, and newly-homebound consumers placed even more online orders — retailers like Amazon shortened delivery times to two days, one day, or even same-day services — and the segment exploded. Related Articles – Maxam Tire Completes Core Size Range for Agrixtra

Ford-E-Transit
Global Tire Manufacturer Ralson Enters US TBR Market

Global tire manufacturer Ralson is entering the U.S. commercial tire market with a new medium/heavy truck tire manufacturing facility and a team of veteran American sales and marketing tire professionals. Ralson debuted its products for the US with its American team at the 2022 SEMA Show in Las Vegas. Related Articles – Hankook Tire Launches

Michelin Releases Agilis HD Z as New Urban and Regional Tire

Michelin North America has released the Michelin Agilis HD Z 19.5 in two sizes to offer fleets with light and medium-duty vehicles durable, long-lasting tires optimized for the stresses of urban and regional environments. The Agilis HD Z 19.5-in. tires will replace the Michelin XZE in two current sizes (225/70R19.5 LRG and 245/70R19.5 LRH) in

Michelin-Agilis-HD-Z-Tire
Yokohama Tire Launches the 716U UWB Regional Drive Tire

Yokohama Tire’s newest commercial tire – the 716U ultra wide-base – is a weight-savings drive tire that carries more profitability for fleets, the company says. It is available now in the US in size 455/55R225. Related Articles – Vredestein Launches New Pinza H/T in US – Goodyear Adds Wrangler HT Tire to Light Truck Lineup

Yokohama-Tire-716U-UWB-Sidewall

Other Posts

Continental Debuts Enthusiast-Driven ExtremeContact Sport 02

From timed autocross laps to drifting on a skid pad and mastering knee-jerk braking and turns on a raceway, dealers, influencers and members of the media were treated to a crash course in performance racing while testing out Continental’s newest UHP summer tire, the ExtremeContact Sport 02. Related Articles – BKT Tires Launches Agrimaxfactor Tire

Conti-extremecontact-02-closeup
BKT Tires Launches Agrimaxfactor Tire For Tractors

BKT has launched the Agrimaxfactor, a new tire series for tractors for transport and soil tillage operations. Related Articles – Continental Tire Launches ExtremeContact Sport02 – BKT Launches EM 933 Super Excavating Tire – Kenda Unveils Vezda Touring 4S, its First ‘Four-Season’ Offering The company says it developed the series in response to the request

BKT_AGRIMAXFACTOR_Field
Michelin’s Enviro System Unveils Tire with 58% Sustainable Materials

Michelin says its subsidiary Scandinavian Enviro Systems is the first tire manufacturer in the world to unveil tires with a high proportion of environmentally sustainable materials that have been approved for use on ordinary road vehicles. These include tires for buses and cars containing recovered carbon black from Enviro, among other materials. Related Articles –

Michelin-Enviro-Tire
Cooper Unveils Largest Tire in its Discoverer Rugged Trek Line

At the annual SEMA Show in Las Vegas, The Goodyear Tire & Rubber Company unveiled the biggest tires yet in its Cooper Discoverer Rugged Trek tire line. Designed for lifted pickup trucks, these all-new, large-sized tires feature signature Cooper Knife-Edge and Mountain Pass customizable sidewall designs and will be available to consumers in early 2023.