TM 9-2320-280-20-1
REFERENCE INFORMATION
Change 1 2-401
TRANSMISSION SYSTEM
(3L80)
1.Position transmission shift lever in D (drive) and accelerate vehicle from 0 mph. A 1-2 and 2-3 shift should occur at all
throttle openings. Allow vehicle to coast down to about 0 mph and 3-2 and 2-1 shifts should occur.
2.Position transmission shift lever in 2 (low two) and accelerate vehicle from 0 mph. A 1-2 shift should occur at all throttle
openings. No 2-3 shift can be obtained in this range. A 1-2 shift in 2 is somewhat firmer than in D. This is normal.
3.Position shift lever in 1 and accelerate the vehicle from 0 mph. No upshifts should occur in this range.
4.Position shift lever in D and with the vehicle speed at approximately 35 mph, close throttle and move lever to 2.
Transmission should downshift to 2nd gear. An increase in engine rpm and engine braking effect should be noticed.
5.Position shift lever 2 and with the vehicle speed at approximately 25 mph, close thethrottle and move lever to 1.
Transmission should downshift to 1st gear. An increase in engine RPM and engine braking effect should be noticed.
6. Position shift lever in R and check for reverse operation.
7. Hard shifting may be indicative of an underfilled or clogged system.
Procedure for checking transmission fluid
1. Start engine.
2. Hold down brake pedal and move trans-
mission shift lever through all ranges
including reverse. Leave the lever in each
range for 2 seconds.
3. Engage parking brake and place shift lever
in neutral. Check fluid level on dipstick.
4. Proper level is between FULL and ADD
marks on dipstick.
NOTE
Burnt smell, discoloration, or grit indicates
worn or damaged internal components.
Notify DS maintenance.
Bubbles indicate an overfilled system or air
leaks in the system. Drain the fluid and refill
to proper level. Refer to (para 5-2).
Milky appearance is due to water in the
system. Change the fluid and filter.
Check fill tube for indications of fluid being
blown out. If fluid is being blown out, check
vent line for obstructions, and refill
transmission to proper level. Refer to
(para 5-2).
Transmission fluid coming out of dipstick filler
tube indicates a restriction in the ventilation
system. Check for clogged, melted, or crushed
lines and/or fittings between transmission and
atmosphere vent on air cleaner canister.
Replace where needed. Refer to (para 5-16).
Check fluid for a burnt smell, grit, discoloration,
air bubbles, or a milky appearance.
The kickdown system is used to shift the
transmission to a lower gear under heavy
acceleration. The system also disengages the
engine cooling fan so as to allow maximum engine
power to be used for moving the vehicle.
Road Test Procedure