Symptoms:

  • TCC slip under load
  • No line rise during TCC apply in 4th
  • Overheated converter
  • Loss of lube oil
  • High line pressure with no indication of boost
  • No lockup
  • TCC cycling

Cause:

Excess boost valve bore wear reduces oil pressure to the switch valve, resulting in a partial stroke position, restricting the converter and lube circuits.

Correction:

The Sonnax oversized lockup boost valve restores the proper pressures to the switch valve and main regulator valve, ensuring proper flow through the converter and lube circuit and correcting line pressure.

42RE, 42RH, 46RE, 46RH, 47RE, 47RH, 48RE, A727, A904

Oversized Lockup Boost Valve Kit
Part No. 22771-19K

'90-Later with boost oil deliver tube


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

Chrysler 42-46-47-48RH/RE transmissions are equipped with a lockup boost valve that is prone to wear. When this valve wears, it causes a loss of converter and lubrication flow, which can result in TCC slip and an overheated converter. Lockup boost valve wear also causes excessive line pressure, and line rise during TCC apply or in 4th gear can be lost. Sonnax offers an oversized lockup valve boost kit, 22771-19K, that restores the lockup boost circuit pressures. The lockup boost valve kit will correct TCC apply, lubrication and overheat problems, as well as maintain proper line pressure.

  • Both valves are hard-coat anodized aluminum to resist wear
  • The Sonnax spring is calibrated to match OE pressure with the oversized valves

Fits 90-later with boost oil delivery tube.

  • Lockup Boost Valve
  • Plug Valve
  • Spring
  • Spring Retainer

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.

Chrysler 42-46-47-48RH/RE Valve Body Layout

Chrysler 42-46-47-48RH/RE Valve Body Layout
  • 42RE, 42RH, 46RE, 46RH, 47RE, 47RH, 48RE, A727, A904 Oversized Lockup Boost Valve Kit 22771-19K
  • 42RE, 42RH, 46RE, 46RH, 47RE, 47RH, 48RE, A727, A904 Oversized Lockup Boost Valve Kit 22771-19K

You need this if...

A visual inspection reveals wear, especially at the inboard end and valve plug end. Inspect and vacuum test as shown in illustration.

42RE, 42RH, 46RE, 46RH, 47RE, 47RH, 48RE, A727, A904 Oversized Lockup Boost Valve Kit Vacuum Test Locations