Words by Andrew Middleton, Pictures by Andrew Middleton & Haldon Krog
We were winding our way into Lesotho on our first drive with the new Bridgestone Dueler A/T D693 III, which would put them to the test on every terrain from rock, gravel and tar to mud. Standard fitment on the new Fortuner and Hilux, the D693 III is Bridgestone’s latest foray into the allterrain market and the third iteration of the Dueler name.
As the tyres spun and rocks tumbled under my wheels, the philosophy of the new Duelers began to make sense. Increased wet and dry performance on tar is of paramount concern, but Bridgestone didn’t want to lose any off-road performance. The balancing act between dirt- and tar performance comes down to compounds; and, in this respect, Bridgestone has decided to boost the D693 III’s silica content for added traction.
In developing a tyre, engineers must balance grip, rolling resistance and tread wear − in what’s known as the magic triangle. Increasing one of these properties has always been at the expense of another; that is, until the arrival of silica. Silica is the magical ingredient that somewhat offsets this trade, and by adding more silica to the tyre compound, Bridgestone has managed not only to increase traction on all surfaces, wet or dry, but also to decrease rolling resistance without overly compromising tread wear.
As for the balance of off-road and on-road performance, Bridgestone has increased the strength of the top of the sidewall (nearest to the tread) which obviously increases puncture resistance on difficult terrain like rock, while increasing lateral rigidity in the sidewall for more stable cornering on tarmac.
Because Toyota has chosen this tyre as original fitment for its latest crop of bakkies, the bias toward tar road travel is natural, and the Dueler A/T D693 III should be considered a road-biased tyre with a 70% focus on tar/gravel surfaces. This focus results, apparently, in a tyre with the least rolling resistance by far of any tyre in its class, benefitting customers with reduced fuel consumption amongst the other benefits mentioned. It is thanks in part to the new Dueler that the Fortuner and Hilux get realistic fuel-consumption figures as low as 8l/100km, and that tyres used primarily in this 70/30 ratio still possess the longevity that customers expect.
Improvements over the D693 III’s predecessor include a wider full cap belt and reinforced shoulder blocks for a more even contact patch when cornering, which improves traction and safety. The tread blocks are not as high as those of its predecessor, improving stability by reducing tread flex. While less aggressive in appearance, the new tread pattern and higher silica compound dramatically reduce both rolling resistance and road noise.
Dueler D693 Images
Where we went
With tyres on our mind, it was time to pit all this theory against the real world. Our task would be to drive around 1500km over highways, gravel roads and rock tracks: a true test for an all-terrain. The first challenge was Ongeluksnek Pass.
Located near the small town of Matatiele on the south-eastern border of Lesotho, Ongeluksnek Pass is the rude awakening into Lesotho from the SA side. Consider it an alternative to Sani pass; but, instead of being a graded gravel road crawling with tourists, Ongeluksnek is a genuine challenge – especially in the wet.
Luckily, we had arrived before any major rains. A track of dried black cotton soil, scarred by the trenches dug by 4x4s after rain, winds up the mountain and wiggles its way into the Southern Drakensberg. The pass is tough on tyres; sharp rocks poking from the dark clay are formidable obstacles, and with a 10-hour driving day ahead, punctures were the enemy.
From the rocks of Ongeluksnek, we drove the 120km to Semonkong Lodge on the dodgy, recently-built Chinese tar roads. The tar roads are strewn with boulders: clearly, preventative maintenance isn’t a known term for road builders in high country.
The next day, another 10-hour drive lay ahead. We exited Lesotho, circumnavigated the small country on rough gravel tracks on the South African side of the country, and entered again via Sani Pass. We stayed at the Sani Mountain Lodge for a night before descending the pass and going back to Durban, from whence we’d come.
What had our short but intense trip proven? We learnt that the tyres performed admirably on the convoluted tar roads, as well as on boulders, clay and rocky gravel proving Bridgestone’s theory that, for 90% of adventures, the Dueler D693 III is more than adequate.