4L60, 4L60-E, 4L65-E, 4L70-E

2nd Gear Super Hold Servo Kit
Part No. 77911-03K

.87 Ratio

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Sonnax 2nd gear super hold servo kit 77911-03K for GM 4L60 (700-R4), 4L60-E, 4L65-E and 4L70-E transmissions delivers 18% more apply area than the “Corvette” servo (largest OE). It's the perfect choice for performance applications when a larger-than-OE servo is desired, and its unique design avoids the timing flaws and excessive shock loads found in other aftermarket servos. Combine this servo kit with Sonnax 4th gear servo 77767K for unmatched holding power and shift performance that's an easy in-vehicle install.

  • 18% More apply area than OE "Corvette" servo
  • Maximizes holding power in 2nd gear with more positive 1-2 and 2-3 shifts
  • Upgraded dual Viton® seals ensure positive band apply/release and eliminate cross leaks
  • Chromoly steel apply pin is longer than longest OE pin and features added seals to reduce leakage of 3rd gear pressure
  • Servo and piston made from durable billet aluminum
  • 2nd Gear Piston
  • Separator
  • Apply Pin
  • D-Rings (2) Small
  • D-Rings (2) Large
  • O-Ring Small
  • O-Rings (2) Large
  • PTFE Seals (2)
  • 4L60, 4L60-E, 4L65-E, 4L70-E 2nd Gear Super Hold Servo Kit 77911-03K


Harness that Horsepower! Your Guide to a Sonnax 4L60/E Level 3 Performance Build