Symptoms:

  • Delayed Forward
  • Delayed Reverse
  • Forward or Low/Reverse clutch distress
  • Damaged valve body casting
  • Low line pressure upon engagement

Cause:

Wear in the bore of the abuse valve can lead to reduced pressure to the clutch.

Correction:

Recondition the bore and install the Sonnax oversized Forward and Reverse abuse valve kit.

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

Oversized Forward & Reverse Abuse Valve Kit
Part No. 77754-58K

Fits in either of two locations.


You need this if... View Instructions Find a Distributor

Continuous oscillation of the Forward and Reverse abuse valves in GM 4L60-E, 4L65-E and 4L70-E units creates bore wear, allowing clutch feed pressure to exhaust. This reduced clutch pressure causes slippage and burn-up. Reconditioning the bore and installing Sonnax oversized Forward and Reverse abuse valve kit re-establishes hydraulic integrity, eliminating clutch pressure loss. The Sonnax oversized replacement valve has extended spool lengths to provide additional sealing contact area. The stabilization flats on the inboard end of the spool maintain OE flow, but provide continual valve support while stroking. An annular groove has been added to prevent side loading and a new spring has been provided for the modified valve length. Sonnax oversized Forward and Reverse abuse valve kit 77754-58K fits either the Forward or Reverse abuse location and includes a replacement bore plug.

  • Eliminates leakage of clutch feed pressure to the exhaust port at the spring pocket
  • One valve and spring combination works for either Forward or Reverse abuse locations
  • Includes replacement abuse bore plug

  • Valve
  • Plug
  • Spring

Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.

GM 4L60-E, 4L65-E, 4L70-E Valve Body Layout

GM 4L60-E, 4L65-E, 4L70-E Valve Body Layout
  • 4L60-E, 4L65-E, 4L70-E Oversized Forward & Reverse Abuse Valve Kit 77754-58K
  • 4L60-E, 4L65-E, 4L70-E Oversized Forward & Reverse Abuse Valve Kit 77754-58K
  • 4L60-E, 4L65-E, 4L70-E Oversized Forward & Reverse Abuse Valve Kit 77754-58K

You need this if...

Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.

4L60-E, 4L65-E, 4L70-E Oversized Forward & Reverse Abuse Valve Kit Vacuum Test Locations