What is the Transmission Valve Body?

The Automatic transmission is a complicated piece of engineering and the up shifting and down shifting are controlled by an item called the Valve body.

The Control Unit

This control unit is at the centre of all functions of the transmission. It contains a maze of channels and directs hydraulic fluid through a series of channels, that activate the appropriate valves to switch on the various clutch packs to give smooth shifts and the correct gear changes for the right driving situation.

Each valve in the unit has a specific purpose and function. Examples of this are the 1-2 shift valve that allows  the valve body to direct oil to one side of the valve ,which then allows movement in one direction to overcome spring tension, this in turn  opens an oil gallery which directs oil through the transmission casing to feed oil into the clutch pack to apply  a series of friction plates.

The main valve that you have direct control over is the manual valve. This valve is connected to the t bar or column shifter, and covers or uncovers various passages depending where you place the t/bar controller .When you place the shifter unit in drive ,the manual valve directs fluid  to  the correct clutch to select first gear to allow fwd movement.  

Computer controlled solenoids

On electronic controlled transmissions which run a computer you also have solenoids that are mounted on the valve body ,this  helps move the appropriate valves to control the shifting more precisely and smoothly. Problems that can occur with this unit are,1 valves jamming due to foreign material (metal or clutch material)floating in the oil,2. valve body bores in the housing wearing due to age .3 solenoids failing.

Remember a small check now can save a larger cheque later

Our Transmissions Services Include:

  • Automatic transmission overhauls
  • Repairs / servicing
  • Coolers supplied & installed
  • Shift Kit installations
  • Reconditioned torque converters
  • Valve Body reconditioning
  • General servicing
  • Clutch replacement & flywheel machining
  • Differential servicing
  • Fault Diagnosis & Troubleshooting
  • Gearbox repair
  • Clutch recalibration
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  • Coolant changes / flushing
  • All Australian & imported vehicles
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  • Torque converter repairs & overhauls
  • General auto warranty servicing
  • Authorised registration inspection (Pink slip)