Yokomo ZS-508S On-Road Differential Threaded Adjusters  [ZS-508S]

How these adjuster screws work

The Yokomo ZS-508S Differential Adjusting Screws serve as a direct replacement component for on-road R/C differentials, intended for tune-up and maintenance tasks. They provide the threaded interface that controls preload and changes how torque is transferred through the gearset, allowing consistent mechanical adjustment during setup.

These screws should be fitted into a compatible differential housing or carrier in lieu of the factory adjuster. Installation involves opening the diff, removing the original adjuster, and reassembling while preserving gear alignment and the condition of lubricants. Use small precision tools and avoid over-torquing to protect the threads.

When tuning, the adjusters permit fine incremental changes to preload and engagement characteristics; even a fraction of a turn can alter handling on sticky tracks. Always verify gear mesh and bearing smoothness after reassembly and confirm the part is compatible with your differential design before use.