After the success story of James Asbury Allison, the visit to the Hungarian production department and the presentation of the multinational's corporate mission, comes the most exciting moment, that of the road tests.
On the square, two identical trucks supplied by Scania welcome us: one equipped with an automated gearbox Opticruise and the other, the red model, with a transmission Allison 3000At the start and on the circuit, the red Scania outstrips the white model, equipped with AMT, the automated mechanical transmission, by at least 100 metres.
It is worth noting a certain disparity, as the two vehicles use completely different systems in terms of gear shift timing: one uses hydraulic pressure, the other an automated clutch.
The test proves to be effective (see video) to understand and compare the qualities between torque converter and automated clutch disc systems.
Diversified fleet of vehicles
Also on test at the forecourt is a 24-year-old American school bus with 430.000 kilometres on the clock, still equipped with the original Allison transmission. In addition, there is an Iveco truck from Team de Rooy, which has a feature that is not too highlighted by the media: it is equipped with an Allison automatic transmission.
We are informed that in 2024 (as in 2023 and 2022...), the team not only won, but also ranked among the top 10 in several editions of the Dakar Rally.
The Armored Tacticians off road
There are numerous opportunities to test vehicles. Among the models available for testing are three tactical vehicles: the Gamma komondor, the Tatra Strength and the Titus (opening photo), together with a URO VAMTAC ST5, which is for sale and therefore exhibited only for viewing. Added to these are the robust Mercedes Zetros, buses and trucks, including fire trucks. And to make the experience even more exciting, there is the opportunity to climb aboard the Dakar Rally truck, which literally took off on the rugged testing terrain.
Armored vehicle doors weigh hundreds of kilos and cannot be opened with the usual movements. In the Titus, for example, a hydraulic piston replaces manual force.
With all-wheel drive systems full-time the accelerator must be pressed down to allow all wheels to work simultaneously and maximize grip, even with the longitudinal and transverse differential locks engaged. The ruts in the ground are now deep and the risk of "slipping" by lifting the wheels and losing grip is high. It is advisable to follow a trajectory that guarantees at least grip on one side of the vehicle. The anti-mine seats detached from the bottom alleviate continuous jolts, while the 4-point belts contain lateral oscillations.
At speed, the armored military vehicles look like hydrofoils; they hurtle across a sea of mud, their engines roaring like those of tanks in battle.
With each release of the gas, the “suction” vibrates in the manifolds with a deep, dull thunder, while the vehicles sink and re-emerge with each impact of the ground, raising splashes of mud instead of waves.
We are stopped, but...
Then comes a climb, preceded by a thick layer of mud that covers more than half of the wheels of the komondor. The vehicle stops, or rather reverses, because not even the torque converter is able to keep it still with its pressure at minimum (the creep). 4x4 enthusiasts call it a “rollback,” a stall and loss of traction that causes you to slide backwards. It settles at the bottom, so we lock the differentials and step on the gas: the wheels scrape the ground with ferocity and noise, the engine screams at full revs and does not seem to be self-limited. After quite a few jolts, the komondor begins to advance and, after a series of notable jolts, we manage to conquer the steep hill. The seat belts prove indispensable and in any case the ceiling has shock-absorbing padding that separates us from the solid steel.
With a cool head, I think it is right to make some reflections on the experience. When we talk about hydraulic transmissions, that is with torque converter, we can say that they are all "fully automatic". However, the interaction offered by the manufacturer can vary. What I noticed is that Allison prefers a fully automatic use, although it is possible to select individual ratios via a keyboard with increasing exclusion or a simpler lever (a feature that, let us remember, characterizes all automatic transmissions). Missing (at least on these versions) are the paddle shifters, perhaps because when driving in automatic mode you rely completely on the convenience of the system, which is an objective aspect today.
The situation is different with other similar and competing systems (hydraulic), which are absolutely valid and not penalizable. In these cases, the offer of greater interaction of the driver - although optional - is more renowned. A concept linked to the skill of the driver that becomes a key component, but it is worth reiterating that the functionality of modern control units, make human action superfluous in any condition; by now a fact.
Combat and off-roading: impressions
The 6x6 Titus It is a 17-ton IMV (Infantry Mobility Vehicle), equipped with an Allison automatic transmission and produced by the French company Nexter. The real strength of the vehicle is the TATRA chassis on which it is built: an engineering masterpiece that integrates the legendary “Central Backbone Tube”. This system encloses the (telescopic) transmission shaft in a central tube, allowing extraordinary performance thanks to independent wheels and suspension, as well as greater ground clearance. Road holding is also impeccable thanks to this solution; in fact, the Titus follows the trajectories like a sports car, despite having three axles, two of which are steering, a configuration that significantly reduces the turning circle, despite its almost 8 meters in length. By exaggerating with the accelerator, we deliberately sought some oversteer. Although the design of the nose may not seem very attractive, that is precisely where its incredible torque is hidden.
No less spectacular is the Iveco Powerstar of the De Rooy team, also equipped with an Allison automatic transmission. During the hours spent on the test track, the vehicle continued to run and jump with unstoppable grit. Thanks to the rigid axles, leaf springs and multiple shock absorbers per wheel, the vehicle found the perfect balance between torque ratio, dimensions and center of gravity, as demonstrated by the successes obtained at the Dakar.
The Mercedes Zetros, tested in the civilian 4x4 version, defies every definition of "truck". With its spring chassis and robust construction, it is a true off-road vehicle. Even tackling a ditch full of water at full speed, it overcame the obstacle without difficulty, apart from a small inconvenience where the windshield seal blew off! The electronic control unit automatically manages the most suitable reductions and gear changes, so, a bit like a lizard, you just have to rely on grip.
Finally, the komondor RDO 3121, an armored reconnaissance vehicle, proved to be aggressive and agile. The driver, with the right amount of skill, simply set the longitudinal or transverse blocks to overcome the most challenging sections. Towards the end of the day, the vehicle suffered a “belly” due to deep ruts in the mud, but still showed an exceptional ability to tackle difficult terrain.
For the sake of completeness, it should be added that the Russian KAMAZ, although not present at the event, is known for its excellent production of armored military platforms and trucks, as well as its outstanding performance in the Dakar rallies. KAMAZ also uses Allison transmission systems.
Interviews
Adjacent to the ACE structure, the constant noises caused by the passage of the Iveco powerstar and Titus make it difficult to capture the audio of the interviews, but we manage to do so... Our interlocutor, Laurent Mazeyrac (photo below), plays a key role in the European panorama of defence vehicles fitted out by Allison.
Why equip a defense vehicle with an Allison transmission?
In defense vehicles, it is essential that operators focus on the mission without having to worry about the transmission line. We offer quality and reliable products, with fully automatic transmissions where you only need to worry about the brake and accelerator, leaving the driver to manage the vehicle with minimal training.
They can focus on the mission without having to worry about shifting gears or choosing the right gear. Simply press the accelerator to move the vehicle and the brake to stop it.
How does fuel consumption compare, especially against competitors?
We have decades of experience in defense programs, especially for the U.S. Government: so a long history of providing reliable automatic transmissions for all defense vehicles.
We are constantly looking for ways to increase efficiency and reduce fuel consumption. Our software optimizes torque delivery to the ground, a major advantage when choosing Allison. Most customers who start with an Allison transmission tend to stay loyal to Allison.
I recently drove De Rooy's Paris-Dakar truck, and the team told me that throughout the Dakar event they never had to touch the transmission nor perform any maintenance on it.
Is it more difficult to equip a vehicle for the Dakar or a defense vehicle?
For us it is not a challenge. We always find a solution, regardless of the weight of the vehicle or its application. We have advanced software that adapts to the behavior of the vehicle, learning to control the optimal gear ratio and timing for a seamless automatic shift.
How might AI interact with Allison's engineering?
Artificial intelligence can greatly improve our software and transmission control systems. It helps us adapt the software to the behavior of the vehicle, ensuring maximum efficiency from the engine. In essence the systems are self-adaptive.
Read the first part: "Power and Precision on the Battlefield: James Allison, the Birth of a Legend"
Read the second part: "Power and precision on the battlefield: production between craftsmanship and innovation"
I would like to thank: Allison Transmission for the opportunity provided and Sjoerd Vos - Marketing Director - Europe, Middle East & Africa (EMEA) for availability and Mr Lauret Mazeyrac, European Sales manager Defense
