ARRMA 1/5 KRATON Front & Rear Differential 30/9T Upgrade - MAKX0930S/2 by GPM  [MAKX0930S/2]

Front & rear complete differential for ARRMA 1/5

This GPM MAKX0930S/2 aftermarket assembly is a drop-in style front and rear differential set designed for ARRMA 1/5 8S platforms. Each differential is supplied fully assembled and uses mixed materials, combining 20CrInTiH hardened steel gears with 7075 aerospace-grade aluminium housings for a balance of strength and weight control appropriate to large-scale RC monster trucks.

The gear train uses helical 30T/9T gear pairs with a 2.0mm module, which improves mesh load distribution compared with straight-cut options while keeping backlash and noise predictable for tuning. The unit is sold without differential oil, so you must fill each diff with the silicone oil viscosity you prefer, the source recommends 100k cSt for maximum locking effect under heavy loads.

Compatibility and fitment follow ARRMA factory layout and this assembly replaces factory part number ARA310937. The set is intended for RC-scale applications only and is suitable for use where higher torque capacity and more robust gear engagement are required, such as aggressive off-road driving and stunt runs on ARRMA 1/5 platforms.

This product is supplied as a single set containing both front and rear assembled differentials in the 30/9T ratio, ready for installation after adding the chosen differential oil.

Use this kit when upgrading ARRMA 1/5 trucks that demand higher gear strength and consistent diff behavior under heavy load, and verify diff oil choice to match your tuning goals before final installation.