Spool Performance – Mercedes AMG 725 9G FX-RT Upgraded Clutch Kit

Spool Performance – Mercedes AMG 725 9G FX-RT Upgraded Clutch Kit

The Spool FX-RT clutch kit upgrades the clutch packs in the Mercedes-AMG 725-series 9G automatic transmission. Spool notes that the factory clutches can begin to slip beyond the mid-700 Nm range, particularly under repeated high load. The increased friction area and proprietary material are rated for up to approximately 1,700 Nm of input torque when the transmission is correctly built and calibrated.

The friction material is designed to tolerate repeated heat cycles and hard use while retaining civil engagement in normal driving. This is an internal transmission build kit, so clutch clearances, wear parts and oil flow should be checked during assembly.

Installation notes

• Installation should be handled by a builder experienced with the 725 9G automatic
• Measure and set clutch-pack clearances during assembly
• Carry out adaptation and calibration for the completed transmission
• Follow the specified break-in procedure before full load