The new six-axle Grove GMK6300L-1 all-terrain crane with Allison's fully automatic 4500 Specialty Series (SP) transmission has been part of the Wiesbauer fleet in Germany since 2018. This new crane replaced the company's previous workhorse GMK6300L, which was also equipped with an Allison fully automatic transmission. The company is indeed pleased with what is currently the only crane with a fully automatic transmission in this vehicle class. The reliability, performance and profitability of the 300 ton (350 USt) crane are unmatched.
Plankstadt, Germany – Multi-axle mobile cranes are heavy and powerful and often only travel at walking speed. They have to be maneuvered with absolute precision on challenging terrain and repeatedly moved from standstill. Transmitting engine power to the axles in as finely controlled manner as possible is a challenge for the cranes' transmission. Conventional dry clutches are pushed to their limits and can overheat and ‘burn.' Allison fully automatic transmissions, on the other hand, are quite different as they use a wear-free torque converter to aid starting rather than a dry clutch. The torque converter not only acts as a hydraulic clutch, but also multiplies the torque and maximizes the engine output. Combined with the uninterrupted transmission of power to the powertrain, this leads to higher productivity and improved driver comfort and control. This makes a huge difference in the field for both the driver and the crane operating companies.
At the end of September 2018, the subsidiary of Wiesbauer GmbH & Co. KG, a heavy-duty logistics provider based in Plankstadt near Heidelberg, took delivery of its new GMK6300L-1 at the Manitowoc plant in Wilhelmshaven.
“We need vehicles that are robust, reliable and cost-effective. We can't afford frequent downtimes and high maintenance costs,” said Norman Weitzel, branch manager of Wiesbauer in Plankstadt. “In addition, we need vehicles also in this class that are easy to operate and can be maneuvered with millimeter precision. Therefore, we have once again decided in favor of a GMK6300L-1 with the torque converter transmission.”
The new Grove GMK6300L-1, which was introduced in March 2018, offers even more power when lifting at great heights and, thanks to the Allison 4500 SP fully automatic transmission, provides outstanding driver comfort and maneuverability.
“For me there's nothing better than a torque converter on a construction site. Maneuvering in inner cities and in tight construction sites is much easier – and more importantly, there's nothing swinging back and forth on the lifting hook,” explained Jörg Haasner, crane driver.
With a maximum capacity of 300 tons (350 USt) and with the main boom fully extended (80 m – 263 ft), the GMK6300L-1 can handle loads of up to 14 tons (15.4 USt). A 37 meter (121 ft) boom extension is available for further operation distance. In total, the crane can reach a tip height of up to 120 m (394 ft). This considerably simplifies tasks such as tower crane erection, situating air conditioning units and elevator equipment on high-rise buildings or chimney work.
The carrier of this two-engine crane is powered by a 430 kW Mercedes Benz engine (Euromot 4/EPA/CARB Tier 4 final) seamlessly matched to the six-speed Allison fully automatic 4500 SP transmission. This pairing allows the GMK6300L-1 to be easily operated on site with a 92.5 t (203,900 lb) counterweight. Axle loads of up to 28 t (30 USt) (per axle) must be moved jerk-free so that the valuable freight does not swing on the lifting hook. This is where the Allison torque converter comes into its own: it enables absolutely smooth and jerk-free starting and braking. The superstructure is powered by a 210 kW Mercedes Benz (Euromot 4/EPA/CARB Tier 4 final) engine.
In contrast to its competitors, Manitowoc Grove has been relying on fully automatic transmissions with torque converters for cranes of this weight and performance class for years.
“The GMK6300L series of cranes are the only ones in their class to have a fully automatic transmission and thus the best operating characteristics on the job,” said Andreas Cremer, global product director for all-terrain cranes for Manitowoc. “The Allison 4500 SP offers a powerful, reliable and cost-effective powertrain solution that has proven itself in the toughest conditions. The electronic controls allow it to adapt to its surroundings and provide self-diagnostics, which make maintenance easier. An optional integrated output retarder offers enhanced braking on slopes and greater safety for the crane operator when driving such a heavy vehicle.”
On public roads and in traffic, cranes must not be a hindrance. A green traffic light requires timely acceleration, even for cranes. This six-axle crane has a top speed of 85 km/h (around 53 mph) when travelling on public roads to the place of operation.
Safe control of heavy loads: Allison fully automatic transmission with torque converter
Allison fully automatic transmissions have been established in the crane market for years where they are appreciated for their reliability. Manitowoc Grove, and its predecessor Krupp Mobilkrane, have been working with Allison Transmission for over 35 years. In addition to the GMK6300L and GMK6300L-1, Manitowoc Grove also offers its GMK7450 cranes with Allison fully automatic transmissions.
“We like to sell cranes with Allison fully automatic transmissions. These are extremely stable systems. I have been in the crane business for 30 years and I have never had trouble with these transmissions.” said Andreas Werner, one of the two owners of KranAgentur Werner GmbH & Co. KG, the exclusive distributor of the Manitowoc Crane Group in much of Germany. “Allison fully automatic transmissions are very user-friendly. All you have to do is select the forward or reverse gear and you can then accelerate promptly. The transmission is low maintenance, robust and reliable. It transmits the engine torque smoothly and without interruption to the wheels which allows prompt and safe starts. This is very important because time is money in the crane business.”
Allison Transmission's 4000 Series is available with close- or wide-ratio gearing and up to seven speeds including two overdrive ratios and a second reverse gear. Engine-driven Power Take-Off (PTO) is available as an option, as is an integral output retarder which provides enhanced vehicle braking and reduces brake wear. Operation is further enhanced by Allison's 5th Generation advanced electronic controls, which also have prognostics capabilities. This enables the 4000 Series to be used in the most challenging conditions.
Allison's 4000 Series is used globally in a wide range of vocational applications, including agriculture, construction, distribution, energy, fire and emergency, mining, municipal and utility services, port services, refuse collection, recreational vehicles and motorhomes, and tractors.
Technical specifications of the new Grove GMK6300L-1
300 t (350 USt)
Maximum main boom
80 m (263 ft)
Maximum tip height
120 m (393 ft)
Allison fully automatic 4500 SP (4000 Series)
Mercedes-Benz OM473LA, 430 kW at 1700 rpm.
Max. torque: 2750 Nm at 1300 rpm.
Mercedes-Benz OM936LA, 210 kW at 2200 rpm.
Max torque 1150 Nm at 1200 rpm to 1600 rpm.
Euromot 4 / EPA /CARB Tier 4 final (non road)