Envalior, General Motors and Schaeffler AG have been recognized with the 2025 Innovation Award in the Powertrain category from the Society of Plastics Engineers (SPE), Automotive Division, for a thin wall electronic throttle control (ETC) actuator gear. The component is designed to deliver high wear resistance, durability and efficiency, while at the same time reducing weight, cost and packaging space in comparison with a conventional actuator gear design. The solution is already applied in two of General Motors' 2025 model year compact SUVs, with Envalior acting as the material supplier and Schaeffler AG serving as the system supplier and material processor.
The award was presented on 5 November 2025 during the 54th Annual Automotive Innovation Awards Competition & Gala, which took place at the Laurel Manor in Livonia, Michigan, USA. The winning project highlights the role of engineering plastics in the ongoing lightweighting of powertrain systems, focusing on geometry optimization and material selection to meet demanding mechanical and tribological requirements in ETC applications. The team leveraged Envalior's high-performance polyamide Stanyl PA46 in combination with glass fiber reinforcement and post-mold heat treatment to realize an ultra-thin, yet robust, gear wall. According to the companies, this allowed significant reductions in gear wall thickness while maintaining precision in gear geometry and delivering improved stiffness and wear resistance relative to a conventional 1.5 mm-thick actuator gear wall. The project was also distinguished by cross-disciplinary cooperation between material experts, component designers and system engineers.
Material selection and gear design
The actuator gear is produced from Stanyl PA46, Envalior's high-performance polyamide. For this application, the team combined a high-flow, wear and friction optimized (W&F-optimized) grade of Stanyl PA46 with 50% or 60% glass fiber reinforcement. This material configuration was selected to support the thin wall design while providing the mechanical strength and dimensional stability required for electronic throttle control.
Following injection molding, the parts undergo a post-mold heat treatment. This step is used to further stabilize the material and enhance mechanical gear performance. According to project information, the combination of high-flow PA46, high glass fiber loadings and controlled post-molding conditioning enabled the realization of precise gear geometry in spite of the reduced wall thickness.
The resulting mid-gear design is intended to ensure precise pedal-to-throttle response in the ETC system. The developers report that the geometry also supports excellent impact absorption, virtually eliminating tooth breakage under operating loads. Together, these features contribute to durability and functional reliability in service.
Performance improvements and savings
Compared with a conventional actuator gear featuring a 1.5 mm-thick wall, the thin wall design reported by the development team delivers both performance and efficiency gains. On the material and component side, the new actuator gear achieves a 30% increase in stiffness and a 20% increase in wear resistance. These improvements are attributed to the selected Stanyl PA46 formulation, glass fiber reinforcement level and the optimized gear structure.
On the system level, the reduced wall thickness enables the electronic throttle control design to achieve measurable savings and packaging benefits. In relation to the 1.5 mm-thick baseline gear, the thin wall actuator gear contributes to:
- 30% weight reduction,
- 20% cost reduction,
- 20% space reduction.
These figures reflect the impact of the new geometry and material combination on mass, material usage and the space required for the actuator assembly in the vehicle's powertrain architecture.
Collaboration across the value chain
The project brought together expertise from different parts of the automotive value chain. Envalior supplied material development and application know-how for Stanyl PA46, General Motors provided system-level requirements and vehicle integration, while Schaeffler AG took on the role of system supplier and material processor, including precision injection molding of the gear.
"This initiative brought together a team of experts from every discipline, and the collaboration was exceptional," said Tony Padden, Envalior Stanyl Technical Application Manager NA. "We overcame challenges, met ambitious targets, and delivered a solution that set a new industry benchmark. I’m proud to have been part of such a rare and successful effort."
The companies underline that the outcome demonstrates how coordinated work between material suppliers, component manufacturers and OEMs can support innovation in powertrain components that are subject to tight packaging constraints and functional tolerances.
Representatives from General Motors, Schaeffler AG, and Envalior are presented with the 2025 SPE Automotive Innovation Award (Powertrain Category) for their ultra-thin wall electronic throttle control actuator gear design.
Application in GM compact SUVs
The thin wall actuator gear is already in serial use. The award-winning application features in two of General Motors' 2025 model year compact sport utility vehicles. In these platforms, the gear functions as part of the ETC system, translating driver input at the accelerator pedal into precise throttle body adjustments.
By pairing the high-flow, W&F-optimized Stanyl PA46 formulation with high glass fiber reinforcement and subsequent heat treatment, the development team reports that it has been able to ensure the mechanical and tribological performance needed for these mass-production applications. The design is intended to withstand repeated load cycles and environmental influences over the vehicle lifetime, while contributing to mass and space savings in the powertrain.
"This project exemplifies the power of collaboration and innovation across the value chain," said Jose Chirino, Envalior Technical Director - Americas. "Together with GM and Schaeffler, we’ve advanced what’s possible in precision powertrain components by combining lightweight design with exceptional mechanical performance and reliability."
The award-winning thin wall actuator gear is produced through precision injection molding using Envalior’s high-performance Stanyl PA46 resin.
