SA4x4’s giant all-terrain tyre test

You want tyres fit for the bush, which are also comfortable on tar? Yup, you have entered the realm of All-Terrain Rubber which must grip and grind its way over a variety of surfaces. But which brand is best? The SA4x4 team amassed 17 sets of AT tyres for the biggest local tyre-showdown ever…

The tyres

The tyre market in South Africa is rapidly expanding – in volume as well as in brand diversity. World-renowned manufacturers such as Bridgestone, Goodyear, Continental (General) and Sumitomo (Dunlop) have facilities here, and a plethora of brands is imported through companies like TiAuto, SA Tyre, Stamford, Tubestone, Minty’s and Lombards, to name a few.

We identified at least 26 different brands of AT tyres available locally, and in the end, received the correct type and size of tyre from 16 different makes – BF Goodrich, Bridgestone, Continental, Cooper, Dunlop, Firestone, General, Goodyear, GT Radial, Hankook, Kumho, Michelin, Nexen, Pirelli, Velocity and Yokohama – with Dunlop supplying two different types of AT patterns.

All the members of the South African Tyre Manufacturers Conference (SATMC) – Bridgestone, Continental, Goodyear and Sumitomo Rubber (Dunlop) – entered their tyres, as well as Michelin SA, also representing BF Goodrich.

The Tyre Importers Association of South Africa (TIASA) was also represented – with Minty’s supplying their new Nexen Rodian Pro AT tyres, but not the Toyo Open Country AT, as it was deemed outdated in terms of technology.

Yokohama SA sent a set of their Geolanders, and Lombards entered their Kumho Road Ventures, while TiAuto supplied GT Radial, Hankook and Velocity tyres, but not their Achilles brand − no stock.

We also approached Pirelli SA; but, as the company is expecting a new-generation Scorpion AT soon, they declined the opportunity. However, we purchased a set of Pirellis as we felt it would make the test more representative. We also procured a set of Cooper Discoverer A/T3s for the same reason.

Other imported makes that we would have liked to include were Falken with its Wildpeak AT (importer Stamford did not want to participate), Maxxis (no stock), Mickey Thompson (not available in the correct size) and Windforce (distributor SA Tyre did not want to supply); and we decided not to include Goodride, Federal, Maxtrek and Hercules.

Control measures

For the tests, the following control measures were imposed:

1. A control tyre (Continental CrossContact LX2) with a more on-road bias was specifically chosen to ensure that no AT tyre would gain an advantage.
2. Control runs were regularly completed for the sand-traction and incline-traction tests to establish a reference point, and repeated during testing to reconfirm this point.
3. For the tar-braking test, each set was warmed up (driven) beforehand and a practice stop done to increase temperature. Tyre pressures were checked before each test-run sequence.
4. At least three runs per tyre were allowed. If a run was not representative, (for instance when the speed was too low before braking,) up to two extra runs were allowed.
5. The best and worst runs were dropped and the average of three runs was recorded.
6. The track for the gravel braking test was swept before every test sequence, and the tracks for the traction and incline tests were regularly checked and maintained.
7. The prescribed tyre pressures were confirmed on the test vehicles before every test.
8. Representatives of all tyre manufacturers were invited to attend the tests. They could also appeal should they notice anything untoward.
9. A technical committee consisting of a representative from Klipbokkop and SA4x4, as well as three different tyre brands, was elected daily to address any problems or complaints. The decision of this committee was final.
10. Representatives from the controlling bodies in the tyre industry (SATMC and TIASA) were invited as independent observers.

The result

In an extremely close-run affair, it was the new General Grabber AT3 that emerged as the best all-rounder tyre in the country, but by only 0.26 percent from the recently released Goodyear Wrangler AT Adventure.

In third position was the Continental CrossContact AT, closely followed by Bridgestone’s Dueler AT 694 and the LTX AT2 from Michelin. The difference between the Michelins and the two different Dunlop Grandtrek AT3 tyres (with the older M pattern just edging out the new G specification) was only 0.15 percent.

With a difference of less than two percent between the top three results, it means that, statistically speaking, there is no variance, while the disparities amongst the top seven are also negligible.

Firestone’s Destination AT tyres also fared well, securing eighth position, ahead of the GT Radial Adventuros and Velocity Raptors, with BF Goodrich’s three-ply KO2s placing 11th – even after losing points on the incline traction test.

Failing that test cost the Pirellis, Yokohamas and Kumhos dearly, as they dropped to the bottom of the scoreboard, while the inconsistent performance of the Cooper Discoverers and the Nexen Rodians harmed their overall results.

Taking the findings of an AT tyre test done in 2014 at Klipbokkop into account, the performance of the Hankook Dynapros and the Kumhos were disappointing, while BFG did well with its KO2s, compared to the results of its T/A KO tyres in the 2014 test.

Conclusions

Firstly, given the small points-and-percentage differences in our test results, it is clear one will nowadays not find a low-quality or bad AT tyre distributed through official channels in the country.

Also of interest is how quickly tyre technology is evolving, with synthetic materials playing a bigger role in each new-generation tyre. Not only does this lead to greater competition amongst the brands as they try to find an edge over their opponents, but also to better, safer and more efficient products.

In our tests, the notion that a more aggressive tread pattern would do better off-road did not necessarily prove true, as they confirmed that a smoother tread could be advantageous, especially in sandy conditions.

However, it did confirm that pressures are of utmost importance. Some tyres in our test – such as the BFGs, Coopers, Yokohamas, Velocitys, and perhaps the Kumhos – may have performed better with lower pressures. (However, keep in mind that the other tyres could similarly have performed better.)

That said, some manufacturers are finding better ways to build stronger and lighter AT tyres with high load and speed ratings, AND sturdy sidewalls.

It is therefore imperative that you make very sure for what purpose you are acquiring a specific tyre. If you need to regularly lug heavy loads over long distances, also off-road, rather choose a more robust tyre with a high load rating (120 R or S). If you are going to use your vehicle mostly on-road, and want to transport only light loads, rather opt for a less rugged pattern.

A final word: please do not generalise these specific test results – they were done under a specific set of circumstances, and therefore the outcome won’t necessarily hold true under different conditions. Lastly, always keep in mind a specific tyre’s requirements and limitations before you hit the road – on, or off, the beaten track.

For the full giant tyre test, see the February edition of SA4x4 magazine.