Ramp Up 4R70W Performance & Reliability with the

ULTIMATE Direct Drum Upgrade


SMART-TECH® Direct Clutch Drum & Shaft Kit

It’s easy to eliminate every critical weakness of the OE direct clutch/drum with the revolutionary Sonnax Smart-Tech kit. PROVEN to handle the most extreme horsepower and torque, this all-in-one upgrade delivers the ultimate in shaft and clutch durability for any driver pushing the limits of stock components.

  • One-Piece Design

    Eliminates weak point where drum splines strip & shafts break.

  • Rugged Shaft

    50% thicker & 2X as strong as the best 300M shafts.

  • 17% More Clutch Capacity

    Custom drum & piston hold one extra friction for optimum protection against burn-up.

Sonnax vs OE direct drum and shaft comparison

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