Beefed Up 40T Spool Set Upgrade Kit For HPI RS4 Sport 3 Series On Road RC Cars Featuring Anodized Aluminum Diff Shaft And Steel Gears To Eliminate Differential Play For Rad Traction And Sharp Braking Response

Precision 40T spool upgrade boosts HPI RS4 Sport 3 grip
✔️ Anodized aluminum shaft, steel gears eliminate slip

This single pack upgrades the stock differential for a locked setup on HPI RS4 Sport 3 touring chassis. It delivers straight track control for circuit races and autocross runs.

✅ Complete 40-tooth spur gear and pinion assembly included
✅ Solid anodized aluminum center diffshafts prevent flex
✅ High tensile steel components match HPI OEM mounting points
✅ Includes fresh o-ring seal and printed installation guide

💡 Why lock the rear axle for competitive on road circuit racing?
- Fixed layouts are handy for killing tire chatter during hard launches
- Direct metal to metal contact transfers torque instantly through turns
- Robust construction tolerates sharp curb strikes without losing alignment
- Simple drop in retrofit cuts repair downtime between qualification sessions