Traxxas 10579 Differential Ring and Pinion Gear

The Traxxas 10579 is a set of replacement rear differential ring and pinion gears.

The ring and pinion turn drive from the driveshaft through ninety degrees into the differential, which means every bit of torque the motor produces passes through this pair. They mesh under constant load and are among the more highly stressed gears in the drivetrain.

Ring and pinion are always replaced as a matched pair, and that is why Traxxas sells them as a set. The two wear into each other over time, developing a mating pattern specific to that pair. Fitting a new pinion against a worn ring gear produces poor mesh, noise, and rapid failure, so replacing only one is a false economy.

Symptoms of wear are usually audible before they are visible: whining or grinding from the rear end under power, or a change in noise as the drivetrain loads and unloads. Left alone, worn gears eventually strip teeth and can take other differential components with them.

Note that Traxxas also lists a metal rear ring and pinion set under 10579X at a higher price point, which is the more durable option for higher-power setups.

Genuine Traxxas replacement part for the 4-Tec.