Scania has announced it is introducing a new range of gearboxes that eventually will replace all of its current automated Scania Opticruise solutions. The first member of the new range – G33CM – will be linked to the updated V8s and Scania’s high-output 13-litre engines with 500 and 540 hp.
The new AMT variants are claimed to be around 60kg lighter with all aluminium housings and reduced internal losses and economy gear ratios which Scania claims results in a one per cent improvement in fuel consumption. The company says they also have awideer spread of ratios and are up to 3.5dB quieter.
Scania also points to improved shifting and better drivability and durability as other benefits from the revised transmissions, along with improved retarder capacity and smart PTO solutions, which the company suggest will help ensure internal combustion engines cvontinue as sustainable transport solutions.
Scania says it has invested more than$AUD660million (400 million euros) in the new range to reinforce its position.
“With its benchmark-setting capabilities, these new automated gearboxes ensure Scania’s successful, low-rev and fuel-efficient powertrains will maintain their lead through the new decade,” Scania says .
“This introduction adds yet another vital Scania component to remaining highly competitive in ICE-based powertrains all the way up to 2030,” says Alexander Vlaskamp, executive vice president, head of sales and marketing.
“The new gearbox range is a prime example of Scania’s technological excellence, bringing increased fuel and transport efficiency to our customers in a sustainable way,” he added.
Scania has a long history of offering automated manual gearboxes dating back to the early 1990s under its Opticruise name,.
The question is why would the company invest in developing a new gearbox range when it already is one of the best solutions in the market.
“It is absolutely necessary,” says Alexander Vlaskamp. “Our new gearboxes offer the improvements needed for more efficient and sustainable road transport in the coming decade. A core feature is the wider ratio spread, making them better suited to meet our low-rev engines with extended economy-gearing and reduced fuel consumption.”
The first new gearboxes will be seen coupled to three of Scania’s four Euro 6 V8s and two inline six engines. The new 770 hp V8 will utilise the existing gearbox which is currently mated to the out-going 730 hp engine.
Scania says the new Opticruise gearbox range has no parts in common with the existing range.
“I hate to use that worn cliché about starting from a blank sheet of paper, but that was actually the case,” says Jimmy Larsson, senior manager, head of gearbox development at Scania R&D.
“The team’s assignment was to develop gearboxes that could handle the diverse demands of the next decade, especially regarding fuel consumption, drivability and sustainability. And with the new range, vehicles with high GCM can use fast axle gearing while still maintaining the required startability.”
Scania longstanding philosophy has been centred on low-revs and high torque as key elements for achieving low fuel consumption. If the engine has the torque and stamina to propel the truck at low engine speeds, less fuel is used.
Scania claims the development entailed highly complex computations with a multitude of factors to consider.
“If a favourable cruising speed can be maintained at around, or just above, 1050 engine revolutions per minute, fuel will definitely be saved,” the company said.
Until recently, a typical long-distance truck operated on a 1400 rpm level however the new gearbox range has a significantly wider spread with a true overdrive gear on top and can handle both low and high revs in an efficient way,
The new gearboxes are shorter than the most common Scania gearbox at present, GRS905. By only using two synchromesh gears (compared to seven) between low and high range split, the new gearboxes are shorter and sturdier, with shafts capable of handling more torque. This also enables Scania to use gears with slightly wider cogs that can handle more load and are more durable.
However, removing synchromeshes also place higher demands on the gearbox management system and the overall gear-shifting strategy. As a result all the electronics are new and manage the pneumatic actuators and the shaft brakes (three in total) that are required to deliver swift, smooth and accurate gearshifts.
Scania’s engineers adopted a new approach to reversing. In most gearboxes, selecting reverse entails letting a separate cog-wheel rotate the main shaft in the opposite direction. In the new Scania range, by contrast, the planetary engagement at the output shaft is used.
Reversing is effected by locking up the planetary wheel carrier. This solution allows access to eight reversing ratios at speeds up to 54 km/h (optional). An example of this application would be for tippers reversing over extended distances such as at tunnel construction sites.
The oil change intervals have been greatly improved, due to higher precision and the use of bigger oil filters and high-quality oil.
Power Take Off capabilities are also vital to a huge number of customers. Scania’s new range comes with an abundance of newly developed and clever PTO solutions aiming to fulfil any number of advanced PTO needs requested by our customers.
There will be nine different PTOs available, all offering increased performance, less drag losses and great flexibility via modularity. The EG PTOs are driven directly by the layshaft and are pressure-lubricated by the gearbox. The new interface on the gearbox with a lubrication port means that they can power heavier equipment such as hydraulic pumps.
The EK PTOs (flywheel driven) will consist of a separate unit, mounted between the engine and the gearbox. Four different ratios will be available and the output tower can be mounted in three different positions.
“All-in-all, we have every reason to believe that our new gearbox range is state-of- the-art for powerful truck engines,” says Alexander Vlaskamp, executive vice president, head of sales and marketing at Scania.
“We hope it will support our customers in fulfilling their transportation tasks in a seamless and sustainable way for many years to come.”