Bands; Servos - Jeep cherokee 2000 Service Manual

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DESCRIPTION AND OPERATION (Continued)

BANDS

DESCRIPTION
KICKDOWN (FRONT) BAND
The kickdown, or "front", band (Fig. 47) holds the
common sun gear of the planetary gear sets. The
front (kickdown) band is made of steel, and faced on
its inner circumference with a friction–type lining.
One end of the band is anchored to the transmission
case, and the other is acted on with a pushing force
by a servo piston. The front band is a single–wrap
design (the band does not completely encompass/
wrap the drum that it holds).
Fig. 47 Front Band
1 – FRONT BAND
2 – TRANSMISSION HOUSING
LOW/REVERSE (REAR) BAND
The low/reverse band, or "rear", band (Fig. 48) is
similar in appearance and operation to the front
band. The rear band of the 32RH is slightly different
in that it does not use a link bar, but is acted directly
on by the apply lever. This is referred to as a double–
wrap band design (the drum is completely encom-
passed/wrapped by the band). The double–wrap band
provides a greater holding power in comparison to
the single–wrap design.
OPERATION
KICKDOWN (FRONT) BAND
The kickdown band holds the common sun gear of
the planetary gear sets by applying and holding the
front clutch retainer, which is splined to the sun gear
driving shell, and in turn splined directly to the sun
gear. The application of the band by the servo is typ-
ically done by an apply lever and link bar.
AUTOMATIC TRANSMISSION—30RH
Fig. 48 Rear Band
1 – PLANETARY GEARTRAIN
2 – REAR BAND
3 – LEVER
4 – SERVO
5 – ADJUSTER
LOW/REVERSE (REAR) BAND
The rear band holds the rear planet carrier sta-
tionary by being mounted around and applied to the
low/reverse drum.

SERVOS

DESCRIPTION
KICKDOWN (FRONT) SERVO
The kickdown servo (Fig. 49) consists of a two–land
piston with an inner piston, a piston rod and guide,
and a return spring. The dual–land piston uses seal
rings on its outer diameters and an O–ring for the
inner piston.
LOW/REVERSE (REAR) SERVO
The rear (low/reverse) servo consists of a single
stage or diameter piston and a spring loaded plug.
The spring is used to cushion the application of the
rear (low/reverse) band.
OPERATION
KICKDOWN (FRONT) SERVO
The application of the piston is accomplished by
applying pressure between the two lands of the pis-
ton. The pressure acts against the larger lower land
to push the piston downward, allowing the piston rod
to extend though its guide against the apply lever.
Release of the servo at the 2–3 upshift is accom-
plished by a combination of spring and line pressure,
acting on the bottom of the larger land of the piston.
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