TM-9-2320-280-20 HMMWV Technical Manual Unit Maintenance Volume 2 Download
Page 617 of 953
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.