BEFORE you crack open a catalogue and pore through an endless stream of aftermarket 4x4 products – bullbars, roof racks, tents, lighting – the very first thing that requires attention before you seek adventure are the four black rings of rubber on each corner of your 4x4.
A decent set of tyres, or, more specifically for the kind of driving we do, off-road tyres, are the first nonnegotiable items when it comes to aftermarket support. It is equipment that could leave you high and dry if the tyres are of sub-standard quality or they’re not fit-for-purpose.
“Not all tyres are the same,” said Andrew Collings, marketing manager at Exclusive Tyre Distributors (Cooper, Mickey Thompson tyres). “They may look similar on the outside, but there are so many differences between brands and range.”
“REGULAR wheel alignments and tyre rotations are critical in combatting irregular wear as the leading cause of tyre noise, especially with aggressive off-road tyres that experience increased tread flex as a result of their open tread pattern. Keeping on top of maintenance will extend any tyre’s life, ensuring it performs at its peak for as long as possible,” Steve Burke from Toyo Tires explained.
Steve Burke, Toyo Tires’ technical manager, added: “Interpretation of the traditional off-road tyre categories can vary widely from brand to brand, but a few key priorities across construction, compound and tread design will be shared across the board.”
Simply put, 4x4 tyres can be broken down into categories – Mud Terrain (M/T), All Terrain (A/T) and Highway Terrain (H/T), and there’s also Light Truck (L/T) construction – each with its own strengths and compromises, depending on the kind of driving you have in store.
“The main difference between Highway Terrain, All Terrain and Mud Terrain tyres is the intended purpose,” said Jon Tamblyn, national technical field services and solutions development manager at Bridgestone Australia. “Each application has different characteristics, so the decision as to which way to go should depend on how you intend on using your 4x4.”
So, before you head down to your closest tyre supplier, figure out what kind of driving you’re likely to do consistently and then make a judgement call. There’s no point picking up a set of muddies if your 4x4 doubles as a work-cum-travel machine – unless, of course, you can be buggered changing tyres whenever you get the chance to chase dirt.
“A good quality off-road tyre really comes down to the type of terrain you intend to tackle,” Tamblyn said. “For the wetter environments prone to mud, you should look for wide grooves and lugs for self-cleaning capabilities. The more aggressive the tread pattern, the more it will bite into the surface.
“For dryer climates it is advised to look toward tyres with narrower grooves to aid in the prevention of the case being punctured, a durable tread pattern with wider blocks, and a harder compound for durability.”
Let’s dig a bit deeper.
A HIGHWAY Terrain tyre is what you’ll typically find beneath your vehicle when you leave the showroom floor. These tyres, which have a tread pattern similar to those on a passenger car, are best suited to bitumen as they are light in construction and will often be quiet and smooth. They’ll do the job on mild off-road tracks, but you’ll need to look elsewhere if you’re tackling more serious tracks.
“Highway Terrain tyres are developed with comfort (and) ride quality in mind for the everyday motorist who isn’t using their 4x4 or SUV for off-road use,” said Bridgestone’s Jon Tamblyn. “While they still have limited off-road capabilities, particularly on sand, the Highway Terrain is more for those who use their 4x4 as a road warrior.”
Andrew Collings added that tyres designed for the highway will have less void or space between the tread blocks, and that “it will also have visible channels that run around the circumference of the tyre, improving its resistance to aquaplaning”.
He added there is also more siping – small slits across the rubber to improve traction – for improved wet-weather performance, and that “a good quality tyre should have an extended filler in the bead to improve the lateral stability of a tyre, and a variable reinforcing overlay between the steel belts to improve ride comfort”.
It’s about low noise, wear life and ride comfort, according to Toyo’s Steve Burke. “They will usually feature long-wearing compounds in tread patterns stylistically similar to OE tyres with lighter-duty construction when compared to A/Ts or M/Ts.
“While they can be used occasionally in light off-road applications, they will not supply the same traction or puncture resistance as an A/T or an M/T,” he said.
According to Mick Small, Falken Tyre Australia’s technical service manager, H/T tyres are often misunderstood. “They are perfect for beach trips and very capable performers on dirt roads and fire trails,” he said.
IF DRIVING habits consist of an equal share of bitumen and off-road terrain, the All-Terrain is right up your alley. As its name suggests, an All-Terrain tyre is the Steve Waugh of tyres – the quintessential allrounder. More often than not they’re built stronger than a H/T tyre, so they’ll cope better with rocks and ruts, and they’ll have a more open tread pattern.
“All Terrain tyres are often the sweet spot for across-the-board-capabilities,” Tamblyn told us. “While they are not as comfortable or quiet as a Highway Terrain, they offer excellent capabilities in rocky environments, smooth and rough gravel, and on harsh tracks, while still suitable for everyday use.”
So if your week consists of the Hume Highway Monday to Friday, and then the Vic High Country on weekends, tick the A/T tyre box. “The A/T is often a go-to choice for those who want a tougher tyre for getting off the beaten track on weekends, and still being able to use their 4x4 as a family car,” Tamblyn added.
There are sacrifices, however, as an A/T won’t be as smooth-riding or sharp in its performance as a H/T on tar, and won’t be as capable as an M/T when it gets really rough. But the sacrifices are worth its allround abilities.
“Contrary to popular belief, a true allterrain tyre should feature a deep, balanced tread pattern that’s intended to tackle any terrain it encounters off-road but that will slightly sacrifice on-road performance as a result,” Steve Burke said.
MUDDIES are noticeable by their deep, blocky tread pattern and strong construction. They’ll get you up and over near-impossible rock climbs and muddy slopes that’ll otherwise stump a set of All Terrains – in combination with a well set-up 4x4, of course – but they’ll be harsh and imposing on long stretches of highway due to their construction and tread pattern, and they’ll hike fuel use, too.
“Mud Terrains really come into their element in wet conditions and are designed for superior mud performance, rough gravel and harsh tracks,” said Tamblyn. “For the toughest conditions they are a prime choice, but they are not the most comfortable option on-road because of the noise generated by the rugged and aggressive tread design.”
M/T tyres are designed to find grip when all hope seems lost, and it does this using clever design techniques. “The open tread patterns you see on muddies are designed to dig for traction in loose terrain while self-cleaning as the tyre rotates, with increased tread groove area forming larger, heavier chunks of crud that are more likely to be spun free,” Steve Burke added. “This will then be supported by heavy-duty construction and additional sidewall protection aimed at preventing punctures, especially when a tyre’s exposure to potential stakes is increased by lowering tyre pressures.”
As well as increased fuel use and the drone of fat rubber infiltrating the cabin, the additional weight of the thick sidewalls also means the tyres will be less graceful over bumps and corrugations. “Compounding this is the tendency for open tread patterns to flex when put under extreme load, something that may only present as slight steering vagueness under normal driving conditions but that can cause inconsistencies in traction when braking or turning sharply,” added Steve Burke.
IF A TYRE is stamped with a L/T (Light Truck) designation (as opposed to Passenger construction) it means the tyre is built stronger to both carry more load and be more durable when off-roading. L/T tyres also have a more aggressive tread pattern, provide increased sidewall protection, improved traction, and are more cutand-chip resistant.
“Light Truck construction increases load-carrying ability and puncture resistance through the use of heavyduty materials, often resulting in a thicker, stiffer and heavier tyre than a passenger equivalent,” explained Steve Burke.
The industry experts we spoke to all recommended Light Truck construction for any form of serious off-roading, or for anyone carrying extra weight on their 4x4 via a bullbar, roof rack, etc.
“Don’t compromise on cost because the Passenger constructed tyre is cheaper,” Andrew Collings told us. “As a company who spends a lot of time testing tyres in Australia’s outback, a tyre with a light truck construction is designed to provide the best protection against off-road damage, such as stakes, punctures and tears. Another consideration is that a light truck tyre will carry a load better as they have increased load ratings.”
Jon Tambyn agreed: “With 4x4s continuing to become bigger and heavier from the showroom, a light truck or L/T construction should definitely be a consideration, especially if you plan to add extra bar work, fridges or load-up with supplies and mates when you go 4x4ing.”
However, opting for a set of L/T construction tyres depends on the shape of the vehicle, the operating conditions of the vehicle, the actual usage of the vehicle, and if the size of tyre is offered in the desired brand/pattern with an L/T option, according to Falken’s Mick Small.
WHILE L/T tyres are the recommended choice, Passenger construction tyres can also be of benefit for those who aren’t prone to serious bush-bashing or remotearea travel. “(They) will often have lower load ratings and puncture resistance but will be lighter and more flexible as a result, offering better fuel economy and ride comfort,” said Steve Burke. “Passenger construction tyres will also ‘bag out’ more easily, allowing a relatively small tyre size to offer a large footprint at reduced inflation pressures when driving on soft surfaces like sand; although, considerably larger light-truck construction tyres will provide even greater flotation due to a physically larger footprint while having the ability to safely operate at even lower pressures.”
THINGS can get overwhelming when choosing rubber for the first time, but there’s a simple trick to remember to make the process a little simpler: “When starting out, the easiest way to compare tyres is remember T.C.C: Tread Design, Carcass Construction and Compound,” Collings said. “It will be across these three categories that products will differ.”
For improved traction and further protection, important features of modern tread designs to look for when browsing for new tyres include flex grooves, mud scoops, release dimples and raised rubber ribs.
Another recent innovation is ‘Micro Gauge Sipes’, which are tiny cuts in tyres designed to suck water up and release on highways to prevent aquaplaning. “This innovation improves the wet traction on-road … because they are Micro, they are thinner … brands that don’t use Micro Gauge Sipes tend to cut and chip more as they provide a leading edge to ‘rip’ on rocks and stones,” Collings explained.
An important aspect to consider in regards to a tyre’s carcass is its tensile strength. For example, Cooper uses Super High Tensile in the steel belts and High Tensile in the body ply cords. Collings added: “For those who are going to be doing a lot more off-road driving, consider a tyre with ‘angle ply’ technology.”
A well-designed sidewall is another integral element that makes up a good-quality tyre. “The design/construction of the sidewall of the tyre plays an important part, with off-road stability on dirt roads and the extra stress/load placed on these tyres in the operating conditions these vehicles are used for,” said Mick Small. “Aggressive upper sidewall biters will aid in traction off-road, whilst also adding extra protection from obstacles when aired down.”
He continued: “Carcass plies on their own are only one part of sidewall strength and staking durability. Other elements such as turn-up plies and height of plies, sidewall rubber thickness and density also need attention.”
The most important thing to remember is whether the tyre is right for the kind of driving you plan to do. “With an idea of whether the construction will be lightweight or durable enough for your application, you can then look at the tread pattern to see if they’ll be right for the terrain you plan to cover,” Steve Burke explained. “More open tread patterns will self-clean better in the sticky stuff, and more closed patterns will provide better bite on hard surfaces and flotation on soft surfaces.”
265 = section width (in millimetres)
65 = sidewall aspect ratio (as a percentage of width)
R = tyre construction (in this case, radial)
17 = rim diameter (in inches)
100 = load rating (in this case, 800kg)
T = speed rating (in this case, 190km/h)
A GREAT holiday can turn to crap pretty quickly if you’ve cheaped-out on a set of off-road tyres. Buying from a trusted dealer, distributor or brand may cost you a few pennies in the shortterm, but the benefits far outweigh the negatives in the long run. Then there are things like warranties and R&D, which you can’t always be sure about when you shop online at a website with a dodgy URL.
“There are numerous horror stories of people left stranded after the seller has disappeared offline and having no way of contacting for a warranty if something should ever go wrong,” Collings said.
Premium tyre companies will use the highest-quality materials, and the tyres will be put through exhaustive R&D and testing before consumer consumption.
Bridgestone, for example, invests significantly in R&D both internationally and for Australia’s unique conditions. “We have an extensive testing program which sees car, truck and 4x4/SUV tyres regularly being tested on Australian roads,” Tamblyn said.
Toyo Tires is also renowned internationally for its exceptional manufacturing techniques. And, as Steve Burke explained, “While we find that collaborative development on a global scale regularly results in off-road tyres that excel in Australian conditions, we do still conduct testing against localised criteria as part of our Quality Assurance Program (QAP).”
Burke added that while many cheaper manufacturers will cut corners by replicating popular products with cheaper materials, if you’re familiar with navigating the modern age of knockoff products, the real risk for the savvy consumer comes in selecting a retailer.
“The tyre industry is not alone in being plagued with parallel imports, with old or over-stocked products from other markets dumped into Australia while circumventing the official distribution channels that provide consistency of supply, warranty and after-sales support amongst other things,” he said. “This may seem like a bargain, but the old adage ‘you get what you pay for’ yet again rings true here, so it’s worth thinking about the services you may be sacrificing to save a buck.”
Falken’s Mick Small reiterated that point, emphasising that all Falken tyres are tested in Australia before they’re approved for local sale. He added: “The value in buying locally (rather than on the internet) from a recognised tyre retailer, ensures you source a quality tyre, professional installation and after sales service/support.”
Website: www.toyotires.com.au Toyo’s ‘Open Country’ range provides premium performance on- and off-road while featuring industry-leading balance and surprising sealed road characteristics, covering models like the R/T (Rugged Terrain), A/T, A/T II, M/T, H/T, Q/T (QuietTerrain) and U/T (Urban-Terrain).
Website: www.bridgestonetyres.com.au Bridgestone has a Dueler tyre to cover both punters that love to skip in mud and those that rarely escape the concrete jungle. The premium rubber is available in M/T, H/T and A/T construction.
Website: www.mickeythompsontires.com.au Mickey Thompson has a range of All-Terrain (Mickey All Terrain 38 and Baja Radial ATZ P3) and Mud-Terrain (Deegan 38, Baja Radial MTZ P3 and Baja Radial Claw TTC) tyres. It also stocks competition tyres – Mini Mag, Baja Pro and Claw TTC – if you plan on entering the next Baja 1000.
Website: www.bfgoodrich.com.au BFGoodrich recently launched its all-new KM3 Mud-Terrain tyre, which features massive tread blocks, “mud-phobic” bars, linear flex zones, enhanced grip on slick surfaces and thicker sidewall rubber. The KM3 joins BFG’s top-selling All-Terrain T/A KO2.
Website: www.falken.com.au Falken’s range of 4WD tyres available from local dealers includes the Wildpeak HT, Wildpeak AT01, Wildpeak AT02, Wildpeak AT3W and Wildpeak MT. All Falken products sold by authorised Falken retailers are offered with six years manufacturer’s warranty for defects in materials and workmanship from date of consumer sale.
Website: www.coopertires.com.au Cooper has a variety of premium off-roadfocused tyres currently on the market including HT3, Zeon LTZ, A/T3 light-duty, A/T3 heavy-duty, S/T Maxx and STT Pro. Go online to see which suits your driving habits.
TYRES are assigned a specific speed rating advising the maximum permitted speed of said tyre. For example, a 265/65R17 100T tyre has a speed rating of 190km/h. For safety reasons, it’s recommended to never exceed the max speed rating. And always double-check ratings when purchasing tyres, especially online, as they could invalidate your insurance.
Tyres are also assigned load ratings, which designates how much weight a tyre is designed to carry when operating at its maximum speed rating and inflated to maximum pressure, as the tyre’s load carrying capacity will decrease with reductions in pressure. For example, a 265/65R17 100T has a load rating of 100, which translates to a maximum permissible load of 800kg. Remember, it’s illegal to install tyres with a lower load index than the vehicle manufacturer’s original tyre.
“All tyres come with a load-rating index and a speed-rating index,” said 4X4 Australia’s Fraser Stronach. “What’s important here is that the load rating has to be matched or bettered when replacing an Original Equipment Manufacturer (OEM) tyre while the speed rating can be lower than the OEM tyre. Laws regarding fitting replacement tyres with a lower speed rating vary state by state. Although it may seem counter intuitive, tyres with higher speed ratings have thinner sidewalls, which help limit heat build-up when high speeds are maintained over long periods of time. Unfortunately, thin sidewalls are also more prone to being torn open by anything sharp. As a general rule, anything from a H-rated tyre up won’t survive long off-road. Speed ratings down to ‘N’ are generally permissible when replacing the OEM tyres.”