Automatic Transmission Road Test - Jeep 1979 CJ-5 Technical & Service Manual

2C-8 AUTOMATIC TRANSMISSION
is operating temperature of approximately 170°F
(77°C).
N O T E : If the transmission fluid level is checked at
room temperature of 75 °F (24 °C), instead of at oper-
ating temperature, the level should be about 1/4 inch
(6.35 mm) below the ADD mark on the dipstick. If the
fluid level is correctly established at room temperature,
it should be at the FULL mark on the dipstick when the
fluid reaches operating temperature.
(8) If fluid level is low, add fluid as necessary, reins-
tall and seat dipstick, and check for leaks.
CAUTION: Do not overfill the transmission. Over-
filling will result in fluid foaming (aeration) and con-
sequent loss of fluid from the vent and fill tube. In
addition, foaming will cause fluid overheating, oxida-
tion, and varnish buildup, which can interfere with
valve, clutch, and servo operation.
Fluid Condition
Along with fluid level, it is equally important to check
fluid condition. If the fluid is dark, smells burnt, or
contains heavy accumulations of metal and clutch plate
material, an overhaul may be indicated. Examine the
fluid withdrawn on the dipstick carefully. If any doubt
about its condition exists, drain out a sample for further
inspection.
CAUTION: After completing any repairs that required
draining the transmission, add six quarts of Jeep, Dex-
ron, or equivalent automatic transmission fluid to the
transmission before starting the engine.
mm t e s t •
Before road testing, be sure the fluid level and manual
linkage adjustment is checked and corrected if
necessary.
Note engine performance when road testing. Poor per-
formance will have an adverse effect on transmission
operation.
During the test, operate the transmission in all gear
ranges to check for shift variations and shift speeds.
Refer to the shift speed chart in the specifications sec-
tion. Note whether shifts are erratic, harsh, or spongy,
and if slippage or engine speed flareup occurs during
shifts. Slippage or flareup may indicate clutch, band or
roller clutch problems.
In most cases, a clutch, band or roller clutch that is
malfunctioning can be determined by comparing which
internal units are applied in each gearshift lever posi-
tion as shown in the clutch and band application chart.
NOTE: Analyzing road test results through use of the
Clutch and Band Application Chart will help in deter-
mining which internal unit has malfunctioned.
Clutch and Band Application Chart
P R M
D
2 1
P R M
1
2
3 1 2
1
Forward Clutch m
9
*
• •
m
Direct Clutch
m
•
Front Band
•
Intermediate Clutch
•
Intermediate Sprag
•
•
Rear Band
•
m
Lo Clutch Roller m
m
4 3 0 0 7
Road Test Procedure
D-Range
(1) Shift transmission into D-range and accelerate
vehicle from zero mph.
(2) A 1-2 and 2-3 shift should occur at all throttle
openings. Shift points will vary with throttle opening.
(3) Decelerate vehicle. As vehicle speed approaches
zero mph or k m / h , 3-2 and 2-1 downshifts should occur.
2-Range
(1) Shift transmission into 2-range and accelerate
vehicle from zero mph or k m / h .
(2) A 1-2 shift should occur at all throttle openings.
Shift points will vary with throttle opening. A 2-3 up-
shift should not occur in this range.
(3) Decelerate vehicle. As vehicle speed approaches
zero mph or km/h, 2-1 downshift should occur.
NOTE: The 1-2 upshift in 2-range is somewhat firmer
than in D-range. This is normal.
1-Range
(1) Shift transmission into 1-range and accelerate
vehicle from fcero mph or k m / h .
(2) A1-2 upshift should not occur in this range.
2-Range—Overrun Braking
(1) Shift transmission into D-range and increase
vehicle speed to approximately 30 mph (48 km/h).
(2) At 30 mph (48 km/h), shift transmission into 2-
range. Downshift to second gear should occur immedi-
ately. An increase in engine rpm and an engine braking
effect should also occur.
NOTE: If a hydraulic system pressure test gauge has
been installed, line pressure should change from approx-
imately 70 psi (483 kPa) to approximately 150 psi (1 03k
kPa) when the transmission is downshifted to 2-range.