Article 4E

Front Axles (outboard of the contact surface with the wheel spacer), nuts & retention system

Technical Regulations

Article 4E

FIA Source

Front Axles (outboard of the contact surface with the wheel spacer), nuts & retention system

Chapter: C10.9

In Simple Terms

This rule covers the design and safety of the front wheel axles and their fastening systems. Teams must use approved nut retention mechanisms to prevent wheel nuts from coming loose during a race, ensuring driver safety and preventing dangerous debris on track.

  • Axle geometry outboard of wheel spacers is regulated for consistency and safety
  • Wheel nuts must have a dual-stage retention system to prevent loosening
  • All fasteners and retention mechanisms must meet FIA specifications
  • Design prevents wheels from detaching due to loose nuts during racing
Official FIA Text

Axle geometry lying outboard of the contact surface with the wheel spacers, wheel nut and dual stage mechanism to retain nut if loose. Axle geometry lying outboard of the contact surface with the wheel spacers, axle nuts, wheel nut, fasteners, and wheel nut retention system.

front axlewheel nutretention systemfastenerswheel spacer
2026 Season Regulations