Overview
Replace the cracking factory plastic differential case on your Traxxas Revo or E-Maxx with the Hot Racing Aluminum Differential Case. CNC-machined from solid aluminum and finished with a clean blue anodized coating, this direct replacement for the Traxxas TRA3978 differential case delivers far greater rigidity and durability than the stock plastic part — essential for high-power brushless and high-torque applications.
A simple, drop-in upgrade that solves one of the most common diff case failures on these big Traxxas platforms.
Key Features
- CNC-machined aluminum construction
- Blue anodized finish
- Direct replacement for Traxxas TRA3978 plastic diff case
- Compatible with Traxxas TRA5382X diff gear set
- Includes mounting screws
Performance Benefits
- Eliminates cracked plastic diff case failures
- Far more rigid than stock plastic case
- Long service life under brushless power
- Premium blue anodized appearance
Usage Notes
Reuses stock steel axial guide and gasket from the original TRA3978 plastic diff case — keep these during disassembly. Use only silicone diff lube during assembly. Apply thread-locker on screws to prevent loosening. Important: Do not over-tighten the case screws.
Technical Specs
- Material: CNC-machined aluminum
- Finish: Blue anodized
- Out Drive Plate Length: 9.5mm
- Out Drive Plate Diameter: 24.3mm
- Diff Case Length: 14.0mm
- Diff Case Diameter: 25.5mm
- Replaces: Traxxas TRA3978
- Compatible Gears: TRA5382X diff gear set
What's Included
- One (1) blue aluminum differential case
- Four (4) screws
Fitment
- Traxxas Revo
- Traxxas E-Maxx
- Other Traxxas vehicles using TRA3978 diff case and TRA5382X gear set
Summary
The Hot Racing Aluminum Differential Case is the right durability upgrade for Revo and E-Maxx owners running brushless power. Solid aluminum, clean blue finish, drop-in fit — install it once and forget about cracked diff cases.