The VLPS

摘要

Chrysler introduced a Variable Line Pressure Solenoid to the existing 41TE (A604) and 42RLE transmission as early as 2007. The addition of this solenoid includes the use of a transducer to verify line pressure control as feedback to the computer. 41TES and 42RLE-VLP are the new designations for the units equipped with the added solenoid and transducer. Its purpose is simple - to improve fuel economy. Typically, factory predetermined line pressures in drive runs approximately 120-130 psi, while reverse is usually in the range of 180-190 psi. The shift solenoids double as clutch pressure control solenoids controlling the rate in which a clutch is applied during both a garage shift into gear and shifting from one gear to the next. Once into gear, the full predetermined line pressure is applied to the clutch. This means that at idle, in drive or reverse, the engine is driving the pump through the torque converter at 120 or 180 psi. Lowering line pressure under these conditions causes the engine to not work as hard, increasing fuel economy.