Axial has just announced a new heavy duty ring and pinion gear set for the Yeti XL. They are direct replacement pieces and according to Axial they can be installed without shims. You can find out more from Axial below.
From Axial
Spiral cut gears are known for their durability and efficiency, which in turn produces less heat and reduces gear noise. That all translates in stronger, quieter gears ready for heavy-duty demand.
• Genuine Axial spare parts
• Spiral cut hardened machine cut gears
• Improved durability
• Direct replacement Yeti XL gears (replaces AX31053, shims NOT required)