General Description And Operation - ATSG FORD 4R100 Manual

TRANSMISSION
DESCRIPTION AND OPERATION
General Description
The Ford 4R100 automatic transmission is a four
forward speed unit with electronic shift control. It is
designed for longitudinal powertrains for rear wheel
drive vehicles.
The 4R100 transmission features a four element
torque converter design that includes Torque
Converter Clutch (TCC) and a gear train that includes
three planetary gearsets.
Some models provide for Power Take Off (PTO)
operation in all transmission shift lever positions.
During PTO operation in OD, 4th gear is disabled.
The hydraulic control system of the 4R100 unit has
five electronically controlled solenoids for:
Shift feel, through line pressure control.
Shift scheduling, through shift valve position.
Engine braking during coast conditions.
TCC apply (On/Off or Modulating).
Major Internal Components
"Seven Friction Apply Elements"
Intermediate Band
Coast Clutch, Multi-disc
Overdrive Clutch, Multi-disc
Intermediate Clutch, Multi-disc
Direct Clutch, Multi-disc
Forward Clutch, Multi-disc
Low/Reverse Clutch, Multi-disc
"Three One-Way Clutches"
Overdrive Roller Clutch
Intermediate Sprag
Low Roller Clutch
"Three Simple Planetary Gearsets"
Overdrive
Forward
Reverse
"Typical" Shift Quadrant Indicator
P R N D 2 1
4
Technical Service Information
Copyright © 2003 ATSG
Figure 2
AUTOMATIC TRANSMISSION SERVICE GROUP
Shift Quadrant Indicator
Vehicles equipped with the 4R100 transmission have
a Transmission Control Switch (TCS), also referred to
as "Overdrive Cancel Switch", and a Transmission
Control Indicator Lamp (TCIL), located on the end of
the manual gear shift lever, as shown in Figure 3. The
TCS is a momentary contact switch.
switch is pressed, a signal is sent to the PCM to allow
automatic shifts from 1st to 4th gear or from 1st to 3rd
gear. After the TCS has been pressed the PCM turns
on the TCIL lamp ("OFF"), to indicate that overdrive
has been canceled, as shown in Figure 3.
The shift quadrant has the following positions, as
shown in Figure 2: P, R, N, D , 2 and 1.
D position (TCS OFF) provides 1-2-3-4 automatic
upshifts and downshifts. Coast braking occurs in 4th
gear. (TCIL Not Illuminated)
D position (TCS ON) provides 1-2-3 automatic
upshifts and downshifts. Coast braking occurs in 3rd
gear. (TCIL Illuminated)
2 position provides a pull-in shift to 3rd gear with
coast braking. After an automatic downshift, a 2nd
gear hold occurs with coast braking.
1 position provides a pull-in shift to 2nd gear with
coast braking. After an automatic downshift, a 1st
gear hold occurs with coast braking.
Figure 3
When this
TCS
SWITCH
OVERDRIVE OFF OVERDRIVE OFF
TCIL LAMP