Reverse Boost Valve Kit
Part No. K77898

Vehicles with GM 200-4R and 4L60 transmissions often have problems with poor Reverse boost or upshifts in manual low. These are generally caused by a worn Reverse boost valve sleeve or wear at the pump body. Sonnax offers a larger ratio (.283") Reverse boost valve kit K77898 to restore the hydraulic integrity of the assembly.

TV Boost Valve Kit
Part No. 77917-471

.471" Dia., O-ring style

A common problem in GM 4L60 transmissions is burnt bands and/or 3-4 clutches. This failure can be reduced by eliminating throttle boost oil leakage. Sonnax TV boost valve kit 77917-471 will eliminate these problems for a variety of applications. For a higher pressure boost, use TV boost valve kit 77917-500.

• Boost valve and sleeve are made from hardened steel for better wear resistance
• O-rings on sleeve separate throttle pressure and reverse boost circuits, providing additional protection against cross leaks
• O-rings prevent loss of oil between the outside diameter of the throttle valve sleeve and pump body

TV Boost Valve Kit
Part No. 77917-500

.500" Dia., O-ring style

A common problem in GM 4L60 transmissions is burnt bands and/or 3-4 clutches. This failure can be reduced by eliminating throttle boost oil leakage. Sonnax TV boost valve kit 77917-500 will eliminate these problems for a variety of applications, and will boost pressure higher than TV boost valve kit 77917-471 due to the increased .500" valve spool ratio.

• Returns higher pressure than OE-ratio valve
• Boost valve and sleeve are made from hardened steel for better wear resistance
• O-rings on sleeve separate throttle pressure and reverse boost circuits, providing additional protection against cross leaks
• O-rings prevent loss of oil between the outside diameter of the throttle valve sleeve and pump body

Pressure regulator valve

The OE pressure regulator valve is prone to rusting in the bore of valve body cores, and is often prone to damage during removal. This direct replacement pressure regulator valve allows salvage of these cores. Slight modifications to the size, number and location of the annular grooves provide better hydraulic sealing and prevention of side-loading for this replacement valve.

• Replacements not available
• Improved hydraulic seal
• Reduced side-loading
• Drop-in replacement with improved tolerances

 Boostvalve TH400 Standard

Vehicles with a GM 400 transmission frequently have poor line rise, soft 1-2 and/or 2-3 shifts and/or reverse engagement difficulties. These problems can be caused by the reciprocating boost valve wearing the inside diameter of the boost sleeve. When this occurs, oil that enters the modulated throttle valve orifice leaks past the boost valve and exhausts through the reverse orifice or to the sump, resulting in poor line rise. Reverse oil also can exhaust both to the sump and back through the modulated TV orifice. The outside diameter of the boost sleeve also allows some leakage through the pump body, which can increase boost oil loss. Sonnax boost valve kit 34910-01K eliminates the above problems by restoring hydraulic integrity and providing a positive seal with the pump bore. Valve and sleeve manufactured from high-quality steel O-rings provide additional protection against leakage through the pump body to assist in maintaining pressure in the circuits which supply the boost valve Kit uses the same valve spool diameters as the OE version to retain factory shifts

Adapter Press.mod.valve ZF5HP19 OS

• Adapter Plate 
• Screws (2)
• Washers (2)

 In certain applications, use of this adapter plate is strongly recommended to secure the valve body to the VB-FIX. See related parts for details.

Tool Mod.valvekit PCA, PCB 5R55N OS

• Reamer 
• Reamer Jig 
• Guide Pin 
• Dremel Bit 

 Tool Kit for 56947J-49K

Tool Press.reg.valve 5R55N Oversize

• Reamer 
• Reamer Jig 
• Guide Pin 

Reamer TCC cntr.valve 5R55N, 5R55W

• Reamer 
• Reamer Jig 
• Guide Pin 

 Tool Kit for 56947J-05K

Tool Press.mod.valve ZF5HP19 OS

• Reamer 
• Reamer Jig 
• Guide Pin 

Tool Kit for 85755-03K

Tool Lubri.valve kit ZF5HP19

• Reamer 
• Reamer Jig 
• Guide Pin 

 Tool Kit for 85755-07K

Boostvalve C6 HP Clicker type

• Valve 
• Sleeve 
• O-Rings (3)

 Fits clicker style units, '76-earlier

NOTE: 

A number of boost valve kits are available for this unit:

• Normal line pressure boost (gas ratio): Kits 36946-01K, 36946-04K and 36941-01K.
• Increased line pressure boost (diesel ratio): Kits 36946-02K and 36946-03K are recommended for all heavy-duty applications.
• Kit 36941-01K works in early model "clicker" versions with screw on boost valve end plate.
• Kits 36946-01K, 36946-02K and 36941-01K include O-rings to provide additional protection against both cross leakage and oil exhausting through the valve body bore.

Boostvalve C6 OE-style Diesel

• Valve 
• Sleeve 

 For diesel-ratio units

• Diesel-ratio kit restores OE boost pressure
• Sleeve manufactured from highly wear-resistant aluminum
• Hardcoat anodized aluminum valve combats premature wear

Boostvalve C6 OE-style Gas

• Valve 
• Sleeve 

 For gas-ratio units

• Gas-ratio kit restores OE boost pressure
• Sleeve manufactured from highly wear-resistant aluminum
• Hardcoat anodized aluminum valve combats premature wear

Converter regulator valve AX4S OS

• Valve 
• Inner Valve Body Clip 
• White Spring 2-Spool OE Application
• Black Spring 4-Spool OE Application