GPM Racing Hardened Steel #45 Rear Differential Ring Gear & Pinion Gear for Traxxas 1/10 MAXX (TXMS1200RS)

Rear differential ring & pinion kit

This 3pcs aftermarket differential gear set is an RC-scale transmission upgrade intended for TRAXXAS MAXX monster truck differentials. The kit replaces the stock rear ring gear and pinion with hardened steel #45 components and includes a stainless steel pin to retain the assembly.

In practical terms the hardened #45 steel parts increase wear resistance under repeated loads, and the tighter manufacturing tolerance reduces gear lash so the drivetrain delivers power with fewer shocks and more consistent engagement. This is relevant when tuning diff preload, selecting gear oils, or diagnosing drivetrain noise.

Installation notes: remove the differential case as per your chassis service procedure, swap the ring and pinion, verify pin alignment and endplay, then check mesh and rotate the assembly by hand before reassembly. Use appropriate threadlocker or retaining methods compatible with RC parts if required by your chassis service practice.

Packing includes

• Ring Gear – 1pcs
• Pinion Gear – 1pcs
• Stainless Steel Pin 2.5×13 – 1pcs

Original Name / Part No:

8977

Specifications

• Item Rear differential ring gear & pinion gear 3pc set
• Material Hardened steel #45, stainless steel pin
• Model Number TXMS1200RS
• Compatibility TRAXXAS MAXX

The TXMS1200RS kit provides a direct replacement geared toward smoother rear differential performance on TRAXXAS MAXX monster trucks, useful for hobbyists focusing on drivetrain durability and consistent gear engagement.

This item is compatible with

• TRAXXAS-1/10 MAXX MONSTER TRUCK-89076-4
• MAXX W/WIDEMAXX MONSTER TRUCK-89086-4

What are the machining tolerances expected for this set?

These gears are produced to tighter machining tolerances than typical cast or sintered stock parts, resulting in reduced backlash and improved tooth contact consistency under load.

Is heat treatment applied to the #45 steel?

The #45 designation indicates a carbon steel grade; proper heat treatment is used to harden the gear surfaces for enhanced wear resistance in high stress RC use.

What checks should be made after fitting these parts?

After installation, verify pinion depth, confirm consistent backlash across the ring, rotate the assembly to check for binding, and ensure retaining hardware is secured to recommended torque or threadlocker specification. Write Product Review Please sign in your account before you can write any review. Sign In Close

Made to order: GPM Racing parts are shipped to us from GPM’s factory, so please allow around 14 days for dispatch.