TM 9-2320-280-20-2
5-21. TRANSMISSION ROAD TEST
This task covers:
a. Road Test (3L80)
b. Road Test (4L80-E)
INITIAL SETUP:
Tools
Equipment Condition
General mechanic’s tool kit
Transmission fluid at proper level (para. 5-2).
automotive (Appendix B, Item 1)
Adjust manual shift linkage (para. 5-12).
Adjust modulator cable (para. 5-15).
Manual References
TM 9-2320-280-24P
a. Road Test (3L80)
1.
2.
3.
4.
5.
6.
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. Shift points will vary with throttle openings. Allow
vehicle to decrease in speed to 0 mph and 3-2 and 2-1 shifts should occur.
Position transmission shift lever in “2” (low 2) 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). The 1-2 shift in “2”
(low 2) is somewhat firmer than in “D” (drive). This is normal.
Position transmission shift lever in “1” (low 1) and accelerate the vehicle from 0 mph. No upshift
should occur in this range.
Position transmission shift lever in “D” (drive) and with the vehicle speed at approximately 35
mph, close throttle and move transmission shift lever to “2” (low 2). Transmission should downshift
to 2nd gear. An increase in engine rpm and an engine braking effect should be noticed.
Position transmission shift lever in “2” (low 2) and with vehicle speed at approximately 25 mph,
close throttle and move transmission shift lever to "1" (low 1). Transmission should downshift to
1st gear. An increase in engine rpm and engine braking effect should be noticed.
Position transmission shift lever in “R” (reverse) and check for reverse operation.
b. Road Test (4L80-E)
1.
2.
3.
4.
5.
6.
5-46
(overdrive) and accelerate vehicle from 0 mph. A 1-2, 2-3, and 3-4 shift
Position shift lever in
should occur at all throttle openings. Allow vehicle to coast down to about 0 mph and 4-3, 3-2, and
2-1 shifts should occur.
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.
Position transmission shift lever in “2” (low two) and accelerate vehicle from o 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.
Position shift lever in “1” and accelerate the vehicle from 0 mph. No upshifts should occur in this
range.
and with the vehicle speed at approximately 45 mph, close throttle and
Position shift lever in
move lever to ‘3”. Transmission should downshift to 3rd gear. An increase in engine rpm and
engine braking effect should be noticed.
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.
