When discussing iconic supercars like the Amg Mercedes Slr McLaren, the conversation often revolves around its striking design, powerful supercharged V8 engine, and its collaboration between Mercedes-Benz and McLaren. However, one crucial component that often goes unnoticed, yet played a pivotal role in the SLR’s performance, is its transmission: the Mercedes 5G-Tronic.
In the early 2000s, Mercedes-Benz was widely utilizing its 5G-Tronic, also known as the 722.6, five-speed automatic transmission across a vast range of its models. From the luxurious S-Class and E-Class sedans to the sporty SL and SLK roadsters, and even robust G-Class SUVs, the 5G-Tronic proved its versatility. Its application extended beyond Mercedes-Benz, finding its way into Chrysler vehicles, Jaguars, Porsche 911s (996 generation), and Sprinter vans, highlighting its robust design and adaptability.
The author of the original article even found this transmission in their own 2002 Mercedes-Benz C32 AMG. Initially wishing for a sixth gear for improved fuel economy, deeper research revealed the true merits of the 5G-Tronic. This transmission was not just widespread; it was remarkably over-engineered. Estimates suggest it could handle up to 800 lb-ft of torque, a testament to its durability and strength.
This inherent robustness became a key factor when Mercedes-Benz and McLaren engineers embarked on the development of the SLR McLaren. Unlike its contemporary rival, the Porsche Carrera GT, which opted for a manual transmission, the SLR McLaren was designed with an automatic transmission from the outset.
According to a McLaren engineer interviewed by Jalopnik, the decision to use an automatic transmission was primarily driven by the immense torque output of the SLR’s 5.4-liter supercharged V8 engine. This powerplant generated a formidable 617 horsepower and 575 lb-ft of torque. Even by modern standards, these figures are exceptionally impressive. A manual transmission simply wasn’t deemed capable of reliably managing such power in the SLR’s intended performance envelope.
Therefore, Mercedes-Benz confidently selected the tried-and-tested 5G-Tronic for this groundbreaking collaboration with McLaren. It represented the more dependable choice, even as Mercedes-Benz was beginning to introduce its newer 7G-Tronic 722.9 seven-speed transmission.
To further tailor the 5G-Tronic to the SLR’s high-performance character, Mercedes-AMG equipped it with a special “Speedshift R” operating mode. This feature provided drivers with three manual modes, allowing for a more engaging and sporty driving experience when desired.
The 5G-Tronic’s capability to manage substantial torque was further exemplified in subsequent AMG models. The Mercedes-Benz SL65 AMG Black Series, renowned for its monstrous twin-turbocharged 6.0-liter V12 engine producing a staggering 738 lb-ft of torque, also benefited from the five-speed 5G-Tronic transmission. It was simply the transmission robust enough to handle the immense power of these top-tier AMG vehicles.
While Mercedes-Benz eventually transitioned to seven-speed and then nine-speed automatic transmissions in its later models, the 5G-Tronic’s legacy of reliability and cost-effectiveness ensured its continued use for a considerable period. Its enduring robustness even saw it being utilized in vehicles as recent as the JK-generation Jeep Wrangler, underscoring its remarkable longevity and dependable engineering.
In conclusion, while the AMG Mercedes SLR is celebrated for its iconic status and performance, the often-overlooked 5G-Tronic transmission played a crucial role in its engineering success. Its robust design and proven reliability provided the necessary foundation to handle the SLR’s immense power, solidifying its place as an unsung hero in the story of this legendary supercar.
