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  • 2-3 Bind-up
  • 2-3 Flare
  • 3-2 Bind-up
  • No 3rd & 4th
  • 2-4 Band burned
  • 3-4 Clutch burned


Inadequate sealing capacity of OE checkball and seat.


Install Sonnax OE replacement 3rd accumulator checkball and seat.

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

3rd Accumulator Checkball & Seat
Part No. 74480D

Wear or debris can prevent the third accumulator checkball and seat from correctly sealing the 3-4 apply circuit. Installing Sonnax 3rd accumulator checkball and seat 74480D prevents leaks in the circuit and 3-2/2-3 timing issues and prolongs the life of the 3-4 clutch.

March 29, 2017

Transmission Report: Sonnax Voted Tops for Parts & Tools!

Topics: Transmission Report Newsletters Transmission GM 4T65-E Transmission 4L70-E Transmission 4L60-E Transmission 4L65-E Transmission 4L80-E Transmission

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  • 74480d