Vehicles with GM 4L60, 4L60-E, 4L65-E and 4L70-E transmissions often exhibit poor 3-4 shift quality and experience band failure in performance applications. The Sonnax 4th gear super hold dual servo assembly 77767K features 40% more apply surface area for greater holding power.

• 40% More surface area for greater holding power
• Can be used with OE, Corvette or Sonnax performance 2nd gear servo assemblies
• Easy to install – transmission removal is not required
• D-ring seals for improved sealing
• Billet aluminum cover
• These are black with the PATC logo
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