5. Sport Category - Transmissions/Differentials/Transfer Cases

You can add transmission/differential/transfer cases coolers and lines, and replace shifter bushings, as long as you don't replace rubber ones with metal ones.

Sport Category Transmissions/Differentials/Transfer Cases - Full Rules

1. Transmission and differential coolers and lines may be added.

2. Shifter bushings may be replaced; non-metal bushings may not be replaced with metal bushings.