Line Pressure:

Information on the line pressure values and solenoid controls in various models of a transmission system.

For 2001-2003 models, the line pressure value remains fixed at approximately 240-260lbs in all ranges during fast idle. The line pressure will only change when the TCC is applied, which reduces the pressure to 145lbs.

In contrast, 2004-2010 models have an additional on/off pressure control solenoid called “G” to lower the line pressure while the transmission is at idle. When the solenoid is turned on, the line pressure drops to 110lbs at idle. However, as the vehicle starts moving, the “G” solenoid turns off, increasing the line pressure to 240-260lbs. This modification was made to address complaints of pump noise at idle for 2000-03 models.

For 2011-14 models, the “G” solenoid was removed and replaced with an EPC solenoid, which modulates line pressure similar to a 4L80E system. The idle pressure for these models is 75-85lbs in all ranges, while the maximum line pressure in all forward ranges is 175lbs, and in reverse, it is 200-210lbs.

It is important to note that the EPC pressure acts directly on the PR valve and does not have an EPC boost valve. This information will help technicians understand the line pressure values and solenoid controls for various models of the transmission system.

Case Connector