The Spicer TTC Gear Mainshaft, part number 63-8-4 or 6384, is a direct-replacement manual transmission component for heavy-duty applications. This mainshaft gear is sold individually and sourced as a genuine Spicer TTC part. The mainshaft gear is a critical internal transmission component, and using the correct part number is essential for proper fit and function. Pro Gear and Transmission carries this part for customers who need a reliable source for Spicer TTC transmission internals. Not sure this is your part? Give us a call to confirm fitment for your specific transmission.
Features
Spicer TTC Gear Mainshaft, part number 63-8-4 or 6384
Direct-replacement internal manual transmission component
Sold as an individual unit
Genuine Spicer TTC part available through Pro Gear and Transmission
Call to verify proper fit for your specific transmission application
