The Sonnax 10-clutch system increases lockup surface in GM Powerglides for significantly more torque capacity than modified OE drums. The drum and piston accept 10 .060" frictions and 10 .060" thick steels, increasing lockup surface to allow significantly more torque than modified OE drums.

Sonnax 10-clutch drum, hub and piston kit with bearing 28756-16K includes the three essential components for building a 10-clutch drum assembly, plus a pump-to-drum bearing and a a shim. The Sonnax drum has material removed for the kit's bearing, allowing overall stack up to be .060" taller than an OE drum alone. An alternative kit, 28756-15K, is the same overall height as OE, but does not include a pump-to-drum bearing and shim.

• Patented drum, hub and piston system improves clutch capacity for maximum durability
• High-strength drum with reduced rotating mass improves on-track acceleration
• 6061 Forged piston will not crack like cast pistons
• Forged chromoly clutch hub guarantees your power makes it to the wheels
• Thrust bearing used between pump and drum