Chrysler 300/300 Touring/300C, Dodge Magnum. Manual — part 1961

3. Install the Torx

T

socket bolts (3) and torque to 8

N·m (71 in.lbs.).

4. Install a new oil filter (4).

5. Install oil pan (5) and torque the oil pan bolts to 8

N·m (71 in.lbs.).

6. Install the adapter plug (10) into the transmission

housing and tighten the bolt (9) to 2.5 N·m (22
in.lbs.).

7. Check O-ring on plug connector (1), and replace if

necessary.

8. Install the plug connector (1) into the adapter plug

(2). Turn bayonet lock of adapter plug (2) clockwise
to connect plug connector (1).

9. Fill the transmission with the correct oil (Refer to

LUBRICATION & MAINTENANCE/FLUID TYPES -
DESCRIPTION)

using

the

standard

procedure

(Refer to 21 - TRANSMISSION/AUTOMATIC -
NAG1/FLUID AND FILTER - STANDARD PROCE-
DURE - TRANSMISSION FILL).

1 - HEAT SHIELD
2 - ELECTROHYDRAULIC UNIT
3 - BOLT
4 - OIL FILTER
5 - OIL PAN
6 - CLAMPING ELEMENT
7 - BOLT
8 - 13-PIN PLUG CONNECTOR
9 - BOLT
10 - ADAPTER PLUG

21 - 378

AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION

LX

FLUID AND FILTER

DESCRIPTION

The oil level control is located on the electrohydraulic
unit (4) and consists of the float (5) which is integrated
into the electrohydraulic unit. The float is positioned to
plug the opening (6) between the oil gallery (2) and
gearset chamber (1) so that the rotating gearsets do
not splash about in oil as the oil level rises. The oil
level control reduces power loss and prevents oil from
being thrown out of the transmission housing at high
oil temperatures.

OPERATION

With low oil levels, the lubricating oil which flows con-
stantly out of the gearset, flows back to oil gallery (2)
though the opening (6). If the oil level rises, the oil
presses the float (5) against the housing opening (6).
The float (5) therefore separates the oil gallery (2)
from the gearset chamber (1). The lubricating oil which
continues to flow out of the gearsets is thrown against
the housing wall, incorporated by the rotating parts
and flows back into the oil gallery (2) through the
upper opening (arrow).

LX

AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION

21 - 379

DIAGNOSIS AND TESTING

EFFECTS OF INCORRECT FLUID LEVEL

A low fluid level allows the pump to take in air along with the fluid. Air in the fluid will cause fluid pressures to be
low and develop slower than normal. If the transmission is overfilled, the gears churn the fluid into foam. This aer-
ates the fluid and causing the same conditions occurring with a low level. In either case, air bubbles cause fluid
overheating, oxidation, and varnish buildup which interferes with valve and clutch operation. Foaming also causes
fluid expansion which can result in fluid overflow from the transmission vent or fill tube. Fluid overflow can easily be
mistaken for a leak if inspection is not careful.

CAUSES OF BURNT FLUID

Burnt, discolored fluid is a result of overheating which has three primary causes.

1. Internal clutch slippage, usually caused by low line pressure, inadequate clutch apply pressure, or clutch seal
failure.

2. A result of restricted fluid flow through the main and/or auxiliary cooler. This condition is usually the result of
a faulty or improperly installed drainback valve, a damaged oil cooler, or severe restrictions in the coolers and
lines caused by debris or kinked lines.

3. Heavy duty operation with a vehicle not properly equipped for this type of operation. Trailer towing or similar
high load operation will overheat the transmission fluid if the vehicle is improperly equipped. Such vehicles should
have an auxiliary transmission fluid cooler, a heavy duty cooling system, and the engine/axle ratio combination
needed to handle heavy loads.

FLUID CONTAMINATION

Transmission fluid contamination is generally a result of:

•

adding incorrect fluid

•

failure to clean dipstick and fill tube when checking level

•

engine coolant entering the fluid

•

internal failure that generates debris

•

overheat that generates sludge (fluid breakdown)

•

failure to replace contaminated converter after repair

The use of non-recommended fluids can result in transmission failure. The usual results are erratic shifts, slippage,
abnormal wear and eventual failure due to fluid breakdown and sludge formation. Avoid this condition by using rec-
ommended fluids only.

The dipstick cap and fill tube should be wiped clean before checking fluid level. Dirt, grease and other foreign mate-
rial on the cap and tube could fall into the tube if not removed beforehand. Take the time to wipe the cap and tube
clean before withdrawing the dipstick.

Engine coolant in the transmission fluid is generally caused by a cooler malfunction. The only remedy is to replace
the radiator as the cooler in the radiator is not a serviceable part. If coolant has circulated through the transmission,
an overhaul is necessary.

The torque converter should be replaced whenever a failure generates sludge and debris. This is necessary
because normal converter flushing procedures will not remove all contaminants.

STANDARD PROCEDURE

CHECK OIL LEVEL

1. Verify that the vehicle is parked on a level surface.

2. Remove the dipstick tube cap.

WARNING: Risk of accident from vehicle starting off by itself when engine running. Risk of injury from con-
tusions and burns if you insert your hands into the engine when it is started or when it is running. Secure
vehicle to prevent it from moving off by itself. Wear properly fastened and close-fitting work clothes. Do not
touch hot or rotating parts.

3. Actuate the service brake. Start engine and let it run at idle speed in selector lever position

9

P

9

.

21 - 380

AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION

LX

4. Shift through the transmission modes several times with the vehicle stationary and the engine idling

5. Warm up the transmission, wait at least 2 minutes and check the oil level with the engine running. Push the Oil

Dipstick 9336 into transmission fill tube until the dipstick tip contacts the oil pan and pull out again, read off oil
level, repeat if necessary.

NOTE: The dipstick will protrude from the fill tube when installed.

6. Check transmission oil temperature using the appropriate scan tool.

NOTE: The true transmission oil temperature can only be read by a scan tool in REVERSE or any forward
gear position. (Refer to 21 - AUTOMATIC TRANSMISSION- NAG1/TRANSMISSION TEMPERATURE SENSOR/
PARK-NEUTRAL SWITCH - OPERATION)

7. The transmission Oil Dipstick 9336 has indicator marks every 10mm. Determine the height of the oil level on the

dipstick and using the height, the transmission temperature, and the Transmission Fluid Graph, determine if the
transmission oil level is correct.

8. Add or remove oil as necessary and recheck the oil level.

9. Once the oil level is correct, install the dipstick tube cap.

TRANSMISSION FILL

To avoid overfilling transmission after a fluid change or overhaul, perform the following procedure:

1. Verify that the vehicle is parked on a level surface.

2. Remove the dipstick tube cap.

3. Add following initial quantity of Mopar

T

ATF +4, Automatic Transmission Fluid, to the transmission:

a. If only fluid and filter were changed, add 7.0 L (7.4 qts.) of transmission fluid to transmission.

NAG1 Transmission Fill Graph

LX

AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION

21 - 381