
(4) The valve train generates a noise very much
like a light tappet noise during normal operation.
Care must be taken to ensure that tappets are mak-
ing the noise. If more than one tappet seems to be
noisy, it's probably not the tappets.
LEAK-DOWN TEST
After cleaning and inspection, test each tappet for
specified leak-down rate tolerance to ensure zero-lash
operation (Fig. 35).
Swing the weighted arm of the hydraulic valve tap-
pet tester away from the ram of the Universal Leak-
Down Tester.
(1) Place a 7.925-7.950 mm (0.312-0.313 inch)
diameter ball bearing on the plunger cap of the tap-
pet.
(2) Lift the ram and position the tappet (with the
ball bearing) inside the tester cup.
(3) Lower the ram, then adjust the nose of the ram
until it contacts the ball bearing. DO NOT tighten
the hex nut on the ram.
(4) Fill the tester cup with hydraulic valve tappet
test oil until the tappet is completely submerged.
(5) Swing the weighted arm onto the push rod and
pump the tappet plunger up and down to remove air.
When the air bubbles cease, swing the weighted arm
away and allow the plunger to rise to the normal
position.
(6) Adjust the nose of the ram to align the pointer
with the SET mark on the scale of the tester and
tighten the hex nut.
(7) Slowly swing the weighted arm onto the push
rod.
(8) Rotate the cup by turning the handle at the
base of the tester clockwise one revolution every 2
seconds.
(9) Observe the leak-down time interval from the
instant the pointer aligns with the START mark on
the scale until the pointer aligns with the 0.125
mark. A normally functioning tappet will require
20-110 seconds to leak-down. Discard tappets with
leak-down time interval not within this specification.
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Remove the air cleaner.
(3) Remove cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(4) Remove rocker arm assembly and push rods
(Refer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARM / ADJUSTER ASSY - REMOVAL). Identify
push rods to ensure installation in original location.
(5) Remove upper and lower intake manifold
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - REMOVAL).(6) Cut the cylinder head gasket for accessibility if
the end tappets are to be removed.
(7) Remove yoke retainer spider and tappet align-
ing yokes (Fig. 36).
Fig. 35 Leak-Down Tester
1 - POINTER
2 - WEIGHTED ARM
3 - RAM
4 - CUP
5 - HANDLE
6 - PUSH ROD
Fig. 36 Tappets, Aligning Yoke and Yoke Retaining
Spider
1 - TAPPET ALIGNING YOLK
2 - YOKE RETAINING SPIDER
3 - TAPPET
DRENGINE 8.0L 9 - 387
HYDRAULIC LIFTERS (Continued)

REVERSE POWERFLOW
When the gear selector is moved into the
REVERSE position (Fig. 5), the front clutch and the
rear band are applied. With the application of the
front clutch, engine torque is applied to the sun gear,
turning it in a clockwise direction. The clockwise
rotation of the sun gear causes the rear planet pin-
ions to rotate against engine rotation in a counter-
clockwise direction. The rear band is holding the low
reverse drum, which is splined to the rear carrier.Since the rear carrier is being held, the torque from
the planet pinions is transferred to the rear annulus
gear, which is splined to the output shaft. The output
shaft in turn rotates with the annulus gear in a
counterclockwise direction giving a reverse gear out-
put. The entire transmission of torque is applied to
the rear planetary gearset only. Although there is
torque input to the front gearset through the sun
gear, no other member of the gearset is being held.
During the entire reverse stage of operation, the
front planetary gears are in an idling condition.
Fig. 5 Reverse Powerflow
1 - FRONT CLUTCH ENGAGED 5 - OUTPUT SHAFT
2 - OUTPUT SHAFT 6 - INPUT SHAFT
3 - LOW/REVERSE BAND APPLIED 7 - FRONT CLUTCH ENGAGED
4 - INPUT SHAFT 8 - LOW/REVERSE BAND APPLIED
DRAUTOMATIC TRANSMISSION - 46RE 21 - 135
AUTOMATIC TRANSMISSION - 46RE (Continued)

SECOND GEAR POWERFLOW
In DRIVE-SECOND (Fig. 7), the same elements
are applied as in MANUAL-SECOND. Therefore, the
power flow will be the same, and both gears will be
discussed as one in the same. In DRIVE-SECOND,
the transmission has proceeded from first gear to its
shift point, and is shifting from first gear to second.
The second gear shift is obtained by keeping the rear
clutch applied and applying the front (kickdown)
band. The front band holds the front clutch retainer
that is locked to the sun gear driving shell. With the
rear clutch still applied, the input is still on the front
annulus gear turning it clockwise at engine speed.Now that the front band is holding the sun gear sta-
tionary, the annulus rotation causes the front planets
to rotate in a clockwise direction. The front carrier is
then also made to rotate in a clockwise direction but
at a reduced speed. This will transmit the torque to
the output shaft, which is directly connected to the
front planet carrier. The rear planetary annulus gear
will also be turning because it is directly splined to
the output shaft. All power flow has occurred in the
front planetary gear set during the drive-second
stage of operation, and now the over-running clutch,
in the rear of the transmission, is disengaged and
freewheeling on its hub.
Fig. 7 Second Gear Powerflow
1 - KICKDOWN BAND APPLIED 6 - INPUT SHAFT
2 - OUTPUT SHAFT 7 - REAR CLUTCH APPLIED
3 - REAR CLUTCH ENGAGED 8 - KICKDOWN BAND APPLIED
4 - OUTPUT SHAFT 9 - INPUT SHAFT
5 - OVER-RUNNING CLUTCH FREE-WHEELING
DRAUTOMATIC TRANSMISSION - 46RE 21 - 137
AUTOMATIC TRANSMISSION - 46RE (Continued)

DIRECT DRIVE POWERFLOW
The vehicle has accelerated and reached the shift
point for the 2-3 upshift into direct drive (Fig. 8).
When the shift takes place, the front band is
released, and the front clutch is applied. The rear
clutch stays applied as it has been in all the forward
gears. With the front clutch now applied, engine
torque is now on the front clutch retainer, which is
locked to the sun gear driving shell. This means that
the sun gear is now turning in engine rotation (clock-
wise) and at engine speed. The rear clutch is still
applied so engine torque is also still on the front
annulus gear. If two members of the same planetaryset are driven, direct drive results. Therefore, when
two members are rotating at the same speed and in
the same direction, it is the same as being locked up.
The rear planetary set is also locked up, given the
sun gear is still the input, and the rear annulus gear
must turn with the output shaft. Both gears are
turning in the same direction and at the same speed.
The front and rear planet pinions do not turn at all
in direct drive. The only rotation is the input from
the engine to the connected parts, which are acting
as one common unit, to the output shaft.
Fig. 8 Direct Drive Powerflow
1 - FRONT CLUTCH APPLIED 6 - INPUT SHAFT
2 - OVER-RUNNING CLUTCH FREE-WHEELING 7 - OVER-RUNNING CLUTCH FREE-WHEELING
3 - OUTPUT SHAFT 8 - REAR CLUTCH APPLIED
4 - REAR CLUTCH APPLIED 9 - FRONT CLUTCH APPLIED
5 - OUTPUT SHAFT 10 - INPUT SHAFT
21 - 138 AUTOMATIC TRANSMISSION - 46REDR
AUTOMATIC TRANSMISSION - 46RE (Continued)

(15) Check and adjust front and rear bands if nec-
essary.
(16) Connect solenoid case connector wires.
(17) Install the transmission range sensor.
(18) Install oil pan and new gasket. Tighten pan
bolts to 17 N´m (13 ft. lbs.) torque.
(19) Lower vehicle and fill transmission with
MopartATF +4, Automatic Transmission fluid.
(20) Check and adjust gearshift and throttle valve
cables, if necessary.ADJUSTMENTS - VALVE BODY
CONTROL PRESSURE ADJUSTMENTS
There are two control pressure adjustments on the
valve body;
²Line Pressure
²Throttle Pressure
Line and throttle pressures are interdependent
because each affects shift quality and timing. As a
result, both adjustments must be performed properly
and in the correct sequence. Adjust line pressure first
and throttle pressure last.
LINE PRESSURE ADJUSTMENT
Measure distance from the valve body to the inner
edge of the adjusting screw with an accurate steel
scale (Fig. 345).
Distance should be 33.4 mm (1-5/16 in.).
If adjustment is required, turn the adjusting screw
in, or out, to obtain required distance setting.
NOTE: The 33.4 mm (1-5/16 in.) setting is an
approximate setting. Manufacturing tolerances may
make it necessary to vary from this dimension to
obtain desired pressure.
One complete turn of the adjusting screw changes
line pressure approximately 1-2/3 psi (9 kPa).
Turning the adjusting screw counterclockwise
increases pressure while turning the screw clockwise
decreases pressure.
Fig. 343 Valve Body Harness Connector O-Ring Seal
1 - CONNECTOR O-RINGS
2 - VALVE BODY HARNESS CONNECTOR
3 - HARNESS
Fig. 344 Manual Lever Shaft Seal
1 - 15/1688SOCKET
2 - SEAL
Fig. 345 Line Pressure Adjustment
1 - WRENCH
2 - 1±5/16 INCH
21 - 308 AUTOMATIC TRANSMISSION - 46REDR
VALVE BODY (Continued)

REVERSE POWERFLOW
When the gear selector is moved into the
REVERSE position (Fig. 5), the front clutch and the
rear band are applied. With the application of the
front clutch, engine torque is applied to the sun gear,
turning it in a clockwise direction. The clockwise
rotation of the sun gear causes the rear planet pin-
ions to rotate against engine rotation in a counter-
clockwise direction. The rear band is holding the low
reverse drum, which is splined to the rear carrier.
Since the rear carrier is being held, the torque from
the planet pinions is transferred to the rear annulusgear, which is splined to the output shaft. The output
shaft in turn rotates with the annulus gear in a
counterclockwise direction giving a reverse gear out-
put. The entire transmission of torque is applied to
the rear planetary gearset only. Although there is
torque input to the front gearset through the sun
gear, no other member of the gearset is being held.
During the entire reverse stage of operation, the
front planetary gears are in an idling condition.
Fig. 5 Reverse Powerflow
1 - FRONT CLUTCH ENGAGED 5 - OUTPUT SHAFT
2 - OUTPUT SHAFT 6 - INPUT SHAFT
3 - LOW/REVERSE BAND APPLIED 7 - FRONT CLUTCH ENGAGED
4 - INPUT SHAFT 8 - LOW/REVERSE BAND APPLIED
21 - 316 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)

SECOND GEAR POWERFLOW
In DRIVE-SECOND (Fig. 7), the same elements
are applied as in MANUAL-SECOND. Therefore, the
power flow will be the same, and both gears will be
discussed as one in the same. In DRIVE-SECOND,
the transmission has proceeded from first gear to its
shift point, and is shifting from first gear to second.
The second gear shift is obtained by keeping the rear
clutch applied and applying the front (kickdown)
band. The front band holds the front clutch retainer
that is locked to the sun gear driving shell. With the
rear clutch still applied, the input is still on the front
annulus gear turning it clockwise at engine speed.Now that the front band is holding the sun gear sta-
tionary, the annulus rotation causes the front planets
to rotate in a clockwise direction. The front carrier is
then also made to rotate in a clockwise direction but
at a reduced speed. This will transmit the torque to
the output shaft, which is directly connected to the
front planet carrier. The rear planetary annulus gear
will also be turning because it is directly splined to
the output shaft. All power flow has occurred in the
front planetary gear set during the drive-second
stage of operation, and now the over-running clutch,
in the rear of the transmission, is disengaged and
freewheeling on its hub.
Fig. 7 Second Gear Powerflow
1 - KICKDOWN BAND APPLIED 6 - INPUT SHAFT
2 - OUTPUT SHAFT 7 - REAR CLUTCH APPLIED
3 - REAR CLUTCH ENGAGED 8 - KICKDOWN BAND APPLIED
4 - OUTPUT SHAFT 9 - INPUT SHAFT
5 - OVER-RUNNING CLUTCH FREE-WHEELING
21 - 318 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)

DIRECT DRIVE POWERFLOW
The vehicle has accelerated and reached the shift
point for the 2-3 upshift into direct drive (Fig. 8).
When the shift takes place, the front band is
released, and the front clutch is applied. The rear
clutch stays applied as it has been in all the forward
gears. With the front clutch now applied, engine
torque is now on the front clutch retainer, which is
locked to the sun gear driving shell. This means that
the sun gear is now turning in engine rotation (clock-
wise) and at engine speed. The rear clutch is still
applied so engine torque is also still on the frontannulus gear. If two members of the same planetary
set are driven, direct drive results. Therefore, when
two members are rotating at the same speed and in
the same direction, it is the same as being locked up.
The rear planetary set is also locked up, given the
sun gear is still the input, and the rear annulus gear
must turn with the output shaft. Both gears are
turning in the same direction and at the same speed.
The front and rear planet pinions do not turn at all
in direct drive. The only rotation is the input from
the engine to the connected parts, which are acting
as one common unit, to the output shaft.
Fig. 8 Direct Drive Powerflow
1 - FRONT CLUTCH APPLIED 6 - INPUT SHAFT
2 - OVER-RUNNING CLUTCH FREE-WHEELING 7 - OVER-RUNNING CLUTCH FREE-WHEELING
3 - OUTPUT SHAFT 8 - REAR CLUTCH APPLIED
4 - REAR CLUTCH APPLIED 9 - FRONT CLUTCH APPLIED
5 - OUTPUT SHAFT 10 - INPUT SHAFT
DRAUTOMATIC TRANSMISSION - 48RE 21 - 319
AUTOMATIC TRANSMISSION - 48RE (Continued)