Low & Reverse Band Applies

WARNING: This page is about a different car, the 2007 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.

Manual Valve

Line pressure at the manual valve enters the Low fluid circuit. Line pressure is then routed to checkball #8.

#8 Checkball (Low)

Low fluid pressure unseats the #8 checkball, which is located in the valve body. This pressure then routes Low fluid to the 2-3 shift valve.

2-3 Shift Valve

Spring force hold the 2-3 shift valve in the downshifted position. Low fluid passes through the valve and Low fluid enters the Low feed circuit. Low feed passes through orifice #4, and Low feed enters the orificed Low feed circuit. Low feed is then routed to the 1-2 shift valve.

1-2 Shift Solenoid (SS) Valve

When the PCM energizes (turns ON) the 1-2 SS valve, high fluid pressure from the 1-2 SS valve builds at the end of the 1-2 shift valve. This causes the valve to downshift against spring force.

1-2 Shift Valve

Fluid pressure from the 1-2 SS valve holds the 1-2 shift valve in the downshifted position. The valve allows orificed Low feed to pass through the valve and enter the Low & Reverse band reduce circuit. Low & Reverse band reduce is then routed to checkball #6 and to the spring side of the Low & Reverse servo piston.

#6 Checkball (Low Reverse Band Apply and Reduce)

The #6 checkball is located in the valve body. The checkball is unseated by Low & Reverse reduce fluid. This allows fluid to enter the Low & Reverse band apply circuit. Low & Reverse band apply fluid is then routed to the Low & Reverse servo piston where the fluid actuates the piston and applies the Low & Reverse band assembly.