Symptoms:

  • Low line rise
  • Low Reverse boost
  • Soft shifts
  • 2nd Clutch distress
  • 3rd Clutch distress

Cause:

Worn and leaking boost sleeves.

Correction:

Sonnax drop-in Reverse and modulated line boost valve kit provides more sealing area. Sleeves and valves made from high-quality hardened steel to prevent excess wear.

4T60, 4T60-E

Reverse & Modulated Line Boost Valve Kit
Part No. 84754-25K

High Ratio

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

Vehicles with GM 4T60 or 4T60-E transmissions often exhibit such problems as poor line rise, soft shifts, poor Reverse boost, and/or 2nd and 3rd clutch distress. These problems can often be caused by worn and leaking boost sleeves. The OE boost valve spools have very narrow contact surfaces within the sleeves, which contribute to the leakage. Sonnax Reverse and modulated line boost valve kit 84754-25K restores hydraulic integrity to entire bore.

  • Sleeves and valves are made from high-quality, hardened steel to resist wear
  • Valve spools have been lengthened considerably to provide more sealing area with the sleeves
  • Kit includes replacement springs to provide proper calibration for the lengthened valve spools
  • Kit allows replacement of all items together
  • Drop-in Zip Valve™ parts install quickly and easily
Learn More About Zip Valve™ Drop-In Repairs
  • Modulated Line Boost Valve
  • Modulated Line Boost Sleeve
  • Modulated Line Boost Spring
  • Reverse Boost Valve
  • Reverse Boost Sleeve
  • Reverse Boost 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 4T60, 4T60-E Valve Body Layout

GM 4T60, 4T60-E Valve Body Layout
  • 4T60, 4T60-E Reverse & Modulated Line Boost Valve Kit 84754-25K
  • 4T60, 4T60-E Reverse & Modulated Line Boost Valve Kit 84754-25K

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.

4T60, 4T60-E Reverse & Modulated Line Boost Valve Kit Vacuum Test Locations