Investigation of the Relationship Between Wheel Diameter & Gross Vehicle Weight to Achieve Acceptable Brake System Performance

Typically, an automotive manufacturer determines the wheel size (i.e. diameter) for a vehicle program prior to the initiation of the design of the brake system. When this occurs, the opportunity is lost to perform a cost-benefit study on the wheel cost and styling versus the brake system development cost and performance. This can create problems for the brake system if the wheel size is too small relative to the GVWR of the vehicle, potentially leading to one or more of the following:

• Increased brake system development issues
• Increased development costs
• Reduced brake system robustness
• Increased trade-offs between performance and economy
• Increased piece cost
• Increased brake system warranty issues

This paper offers a tool that can be used by vehicle manufacturers and brake system integrators to evaluate the potential for a high level of development difficulty when considering a minimum wheel size for a new vehicle program.