can someone explain this to me!
Normally, line pressure is controlled in a 4l60e by the epc solenoid , but because programing of the ecm controls pressure rise, it can greatly effect the shift quality and holding ability. (this is where a good programmer comes in play)
Transgo came up with a way of controlling line pressure many years ago by using a vacuum modulator, just like many old school transmissions do.
In your case you will not need a vacuum modulator to control line pressure, unless the manufacture of the manual valve body has incorporated one into the design. If so, it will come with the valve body.
Hope this helps you.


