TSB 21-11-97 Rev.A
Reverse Buzz (46RE)
Date: Sep 5, 1997
This is a revised TSB which supersedes a previous TSB.
Models 1996-97 BR (Ram) with
Symptom: A buzz (some call it a
moan) sound when shifting into reverse. This condition may be more noticeable
on a cold vehicle that has been parked outside overnight.
- 1996-1997 (AB) Ram Van/ Ram Wagon
- 1996 AN (Dakota)
- 1996-97 BR (Ram)
Diagnosis: Start with a cold
vehicle (parked outside overnight), start the engine and shift from park to
reverse and from drive to reverse several times while listening for a buzz sound
in reverse. The buzz may be more noticeable with the windows down or from
outside the cab. If the buzz is heard in reverse, perform the repair procedure.
(point of information - CC now has regular 7176 ATF, called CC ATF, and
ATF+2, and ATF+3. The feeling is that eventually all will be ATF+3
which is probably 100% synthetic and OK for all CC automatics.)
04897877AA package, reverse buzz
02464324 gasket, pan
04798233 fluid ATF, +2 Type 7176
03515996 filter, fluid
06030910 Seal, Reaction Pin
Procedure: involves removing
the OD unit, prop shaft(s) and transfer case if necessary, replacing the rear
band adjusting lever, reaction lever and strut with high ratio components along
with replacement of the regulator valve pressure plug and sleeve.
PROPELLER SHAFT AND TRANSFER CASE (IF EQUIPPED)
PAN/FILTER/VALVE BODY REMOVAL
Shift the transmission into park and the transfer case into neutral.
Disconnect the negative battery cable(s).
Raise the vehicle on a hoist.
Remove the transfer case skid pad if so equipped.
Mark the front and rear propeller shafts and U-joints for alignment reference
and remove the shafts.
Disconnect the wires at the vehicle speed sensor.
Disconnect the vent hose and vacuum harness at the transfer case switch.
Disconnect the shift rod from the grommet in the transfer case shift lever,
or from floor shift arm - whichever has easier access.
Support the transmission on a jack stand.
Remove the rear cross member.
Support the transfer case with a jack stand and secure the T-case to the
stand with safety chains.
Remove the nuts attaching the T-case to the transmission.
Move the T-case rearward until it is free of the transmission output shaft.
Lower the jack and move the T-case from under the vehicle.
Remove the gear shift and throttle levers from shaft of valve body.
Disconnect wires at solenoid case connector.
Position a drain pan under the transmission.
Loosen the transmission oil pan bolts and allow the transmission fluid
to drain into the drain pan.
While supporting the oil pan, remove the bolts an lower the pan from the
transmission. Dump the remaining fluid into the drain pan.
Remove the fluid filter from the valve body.
Remove the valve body to transmission case bolts.
Lower the valve body enough to remove accumulator piston and springs.
Work manual lever shaft and electrical connector out of the transmission
Lower valve body, rotate valve body away from case, pull park rod out of
sprag, and remove valve body.
Remove the bolts attaching the OD unit to the transmission.
NOTE: The overdrive unit must be fully supported during removal This
is required to prevent damaging the intermediate shaft. Do not allow the
shaft to support the entire weight of the overdrive unit.
Carefully slide the OD unit off the intermediate shaft. Do not tilt unit
during removal. Keep OD unit as level as possible.
Insert alignment tool 6227-2 into the splines of the planetary gear on
overrunning clutch to prevent the splines from rotation out of alignment.
NOTE: Use care when separating the OD unit from the transmission to
prevent gasket damage.
Remove and retain the overdrive piston thrust bearing and spacer.
NOTE: If misalignment occurs, the OD unit will have to be disassembled
to realign the splines.
REVERSE BAND LEVERS AND STRUT REPLACEMENT
NOTE: The bearing may remain on the piston or in the clutch hub
Inspect the shaft "O" rings and replace them if necessary P/N 06030910.
Compress the rear servo piston enough to permit snap ring removal.
Remove the servo piston snap ring. Use caution when removing to prevent
servo bore scratching.
Remove the rear servo retainer, spring, and piston assembly (Fig 2).
Measure the distance from the end of the rear servo piston plug to the
face of the piston (Fig 3). Record this measurement for future use when
adjusting the rear band.
Reinstall the rear servo retainer, spring, and piston into the transmission.
Secure it with a snap ring.
Install the band adjusting screw (from old lever) and partially install
the new band adjusting lever by pushing the reaction shaft through one
flange of the lever P/N 04897877AA.
Using petroleum jelly, assemble the replacement strut and reaction
lever P/N 04897877AA.
Install the assembled strut and reaction lever inside the adjusting lever
and push the reaction pin completely through the assembly until it is flush
with the back of the transmission case.
Loosen the locknut and unscrew the reverse band adjusting screw (but do
not remove the screw).
Using a small punch and hammer, tap the reverse band reaction pin out from
the front until it can be removed. Remove the shaft so both levers can
be removed (Fig 1). Discard the removed levers and strut.
NOTE: Make sure the strut is installed correctly into the low
reverse band. To check installation, apply the lever by hand and note the
movement of the band. It it is not installed correctly, loosen the adjusting
screw until the strut can be put in place without disassembling the levers.
NOTE: Do not tighten the adjusting screw at this time.
REVERSE BAND ADJUSTMENT
Inspect the gasket to ensure it was not damaged during removal. If damaged,
refer to the service manual for replacement.
Install the thrust bearing and spacer in overdrive unit sliding hub. Use
petroleum jelly to keep it in place.
Carefully slide the alignment tool 6227-2 out of the unit.
Raise the overdrive unit and carefully slide it straight onto the intermediate
Install the attaching bolts and tighten them to 25 ft-lbs (34 Nm) in a
Install transmission mount and tighten to 30 ft-lbs (41 NM)
Connect speed sensors and speedometer wires.
Remove the plug in the rear servo test port.
Based on the measurement taken in step 7 of REVERSE BAND LEVERS AND STRUT
REPLACEMENT select the appropriate size drill bit from the following table:
Insert the butt end of the appropriate drill into the test port 3" deep
and centered beneath the servo plug.
With the bit properly located, tighten the reverse band adjusting screw
to 72 in-lbs (8 Nm) and back off the screw 2 1/4 turns.
Loosen the adjusting screw and repeat step 4. While holding the adjusting
screw, tighten the adj screw lock nut to 25 in-lbs (34 Nm).
Remove the drill bit and replace the rear servo test port plug.
PRESSURE PLUG AND SLEEVE REPLACEMENT
||Drill bit diameter
|Early 96 vehicles
||.115 - .135
||.272 - letter I drill
|Late 96/97 vehicles
||.150 - .170
||.312 - 5/16" drill
RE-INSTALLATION OF REMAINING COMPONENTS
Without disassembling the valve body, remove the regulator valve cover
hiding the pressure plug and sleeve (Fig 4).
Remove the existing pressure plug and sleeve and discard the old parts.
Install the replacement parts from the kit.
Reinstall the regulator valve cover and tighten the screws.
Time allowance: 2.7 hr, add 1.7 hr for 4X4
Place valve body manual lever in low (1 position) so ball on rod will be
easier to install in sprag.
Position valve body in case and work end of park lock rod into and through
pawl sprag. Move rod to check engagement.
Install accumulator piston and springs. The inner spring has a smaller
Swing valve body over piston and outer spring to hold it in place. Align
accumulator piston and outer spring, manual lever shaft, and electrical
connector in case.
Seat valve body in case and install the bolts. Alternately tighten each
bolt to 100 in-lbs (11 Nm).
Install the fluid filter. Replace as necessary (ALWAYS -Dave)
with P/N 03515996.
Install throttle and gearshift levers on valve body manual shaft.
Check and adjust front band.
Connect solenoid case connector wires.
Install the transmission oil pan with a new gasket P/N 02464324. Tighten
the pan bolts to 13 ft-lbs (17 Nm).
If applicable, mount the transfer case on a jack and secure the case with
Align transfer case and transmission shaft and install transfer case on
transmission. Tighten transfer case bolts to 26 ft-lbs (35 Nm).
Connect the vent hose.
Connect indicator switch harness to transfer case if necessary. Secure
wire harness to clips on transfer case.
Align and connect propeller shafts. Tighten attaching bolts to 170 in-lbs
Lower the vehicle.
Fill transmission with mopar ATF +2, type 176 fluid P/N 04798233.
Reconnect negative battery cable and reset radio and clock.
Adjust gearshift linkage and throttle valve cable if necessary.
Thanks to Bob Bergevin and Barry Drodge for supplying this TSB information
This page was edited on: May 3, 2004