TM-9-2320-280-34 HMMWV Direct Support & General Support Maintenance Manual Download
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TM 9-2320-280-34  17-32. TRANSMISSION OIL PRESSURE TESTS (3l80)  This task covers:  a. Oil Pressure Diagnostic Test b. Control Valve and Governor Line Pressure  Test  INITIAL SETUP:  Tools Equipment Condition  General mechanic's tool kit: * Transmission fluid at proper level  automotive (Appendix G, Item 1) (TM 9-2320-280-20).  * Adjust manual shift linkage (TM 9-2320-280-20).  Test Equipment * Adjust modulator cable (TM 9-2320-280-20).  Pressure gauge 0-300 psi (Appendix G, Item 40)  General Safety Instructions  Manual References Direct all personnel to stand clear of vehicle when  TM 9-2320-280-10 conducting pressure test.  TM 9-2320-280-20  Maintenance Level  Direct Support  NOTE  * The testing procedures are for use in conjunction with troubleshooting  instructions in chapter 2. Table 7-5, Oil Pressure Diagnosis, shows possible  causes of transmission malfunctions directly related to oil pressure. Note if  any reading is normal, low, or high.  * The testing procedures in this paragraph applies to vehicles with  3L80 transmissions. Refer to TM 9-2320-280-20 for 4L80-E  transmission oil pressure testing.  a. Oil Pressure Diagnostic Test  1. Remove pipe plug (3) from line pressure port (2) on left side of transmission (1).  2. Connect oil pressure gauge to line pressure port (2).  WARNING  Direct all personnel to stand clear of vehicle before starting engine.  Transmission slipping into gear may cause injury.  3. Start engine (TM 9-2320-280-10) and check for leaks at connections.  4. Bring engine to operating temperature.  5. Place transmission shift lever in "N" (neutral) and operate engine at 1,000 rpm, note pressure  reading. Pressure should be 55-70 psi (379-483 kPa).  CAUTION  Total running time for next five tests should not exceed two minutes.  6. Apply service brakes and place transmission shift lever in "D" (drive), and allow engine to idle, note  pressure reading. Pressure should be 60-85 psi (414-586 kPa).  7. Apply service brakes and place transmission shift lever in "D" (drive) and operate engine at 1,000  rpm, note pressure reading. Pressure should be 60-90 psi (414-621 kPa).  8. Apply service brakes and place transmission shift lever in "2" (low 2) and operate engine at 1,000  rpm, note pressure reading. Pressure should be 135-160 psi (931-1103 kPa).  17-150