Fluid And Filter Diagnosis And Testing Diagnosis And Testing - Causes Of Burnt Fluid; Diagnosis And Testing - Effects Of Incorrect Fluid Level; Diagnosis And Testing - Fluid Contamination; Standard Procedure Standard Procedure - Fluid Level Check - Chrysler Vehicle User Manual

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FLUID AND FILTER
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - CAUSES OF
BURNT FLUID
Burnt, discolored fluid is a result of overheating
which has two primary causes.
(1) A result of restricted fluid flow through the
main and/or auxiliary cooler. This condition is usu-
ally the result of a damaged main cooler, or severe
restrictions in the coolers and lines caused by debris
or kinked lines.
(2) Heavy duty operation with a vehicle not prop-
erly equipped for this type of operation. Trailer tow-
ing 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 sys-
tem, and the engine/axle ratio combination needed to
handle heavy loads.
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 aerates the fluid and causing
the same conditions occurring with a low level. In
either case, air bubbles cause fluid overheating, oxi-
dation 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 eas-
ily be mistaken for a leak if inspection is not careful.
DIAGNOSIS AND TESTING - 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 recommended fluids only.
AUTOMATIC TRANSMISSION - 42RLE
The dipstick cap and fill tube should be wiped
clean before checking fluid level. Dirt, grease and
other foreign material 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 withdraw-
ing the dipstick.
Engine coolant in the transmission fluid is gener-
ally 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 neces-
sary because normal converter flushing procedures
will not remove all contaminants.
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
CHECK
FLUID LEVEL CHECK
The transmission sump has a dipstick to check oil
similar to most automatic transmissions. It is located
on the left side of the engine. Be sure to wipe all dirt
from dipstick handle before removing.
The torque converter fills in both the PARK and
NEUTRAL positions. Place the selector lever in
PARK to be sure that the fluid level check is accu-
rate. The engine should be running at idle
speed for at least one minute, with the vehicle
on level ground. At normal operating temperature
(approximately 82 C. or 180 F.), the fluid level is cor-
rect if it is in the HOT region (cross-hatched area) on
the oil level indicator. The fluid level should be in
COLD region at 70° F fluid temperature. Adjust fluid
level as necessary. Use only Mopar
matic Transmission Fluid.
FLUID LEVEL CHECK USING DRB
NOTE: Engine and Transmission should be at nor-
mal operating temperature before performing this
procedure.
(1) Start engine and apply parking brake.
(2) Connect DRBIII scan tool and select transmis-
sion.
(3) Select sensors.
(4) Read the transmission temperature value.
(5) Compare the fluid temperature value with the
chart.
(6) Adjust transmission fluid level shown on the
dipstick according to the chart (Fig. 154). Use only
Mopar ATF+4, Automatic Transmission Fluid.
(7) Check transmission for leaks.
21 - 141
ATF+4, Auto-