Automatic Transmission
WARNING: This page is about a different car, the 2006 Dodge Magnum, 2006 Dodge Charger, and 2006 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Before attempting any repair on a NAG1 automatic transmission, check for Diagnostic Trouble Codes with the appropriate scan tool.
Transmission malfunctions may be caused by these general conditions:
- Poor engine performance.
- Improper adjustments.
- Hydraulic malfunctions.
- Mechanical malfunctions.
- Electronic malfunctions.
- Transfer case performance (if equipped).
Diagnosis of these problems should always begin by checking the easily accessible variables: fluid level and condition, gearshift cable adjustment. Then perform a road test to determine if the problem has been corrected or if more diagnosis is necessary.
| CONDITION | POSSIBLE CAUSES | CORRECTION |
|---|---|---|
|
Harsh N-D Engagement Harsh N-R Engagement |
1. Transmission adaptation/ calibration. | 1. Check for latest level TCM software. Perform the TCM adaptation procedure. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCEDURE) |
| 2. Transmission in limp-home mode. | 2. Check TCM for DTCs. Repair as needed. | |
| 3. Driveline lash/movement. | 3. Check engine mounts, transmission mount, driveshaft couplings, rear crossmember mounts, axle mounts and axle lash. | |
| 4. Converter clutch or lock up control valve malfunction. | 4. Perform converter clutch diagnostics test. Inspect valve body for stuck or sticky lock up control valve. If valve motion is free, replace lock up solenoid and retest. | |
| 5. Valve Body Malfunction. | 5. Inspect valve body for stuck or sticky regulator valve. | |
| 6. Clutch or planetary component damage. | 6. Remove, disassemble and repair transmission as necessary. | |
| Delayed N-D or N-R Engagement | 1. Transmission adaptation/ calibration. | 1. Check for latest level TCM software. Perform the TCM adaptation procedure. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCEDURE) |
| 2. Torque converter fluid drain back, delayed soft engagement. | 2. If vehicle moves normally after 3 seconds of shifting into gear, no repair is necessary. If longer, inspect pump for worn bushing. | |
| 3. Fluid Level Low. | 3. Check and adjust fluid level. (Refer to TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE) . | |
| 4. Filter plugged. | 4. Check TC out pressure, if < 10psi, check for plugged filter. Replace if needed. | |
| 5. Filter damaged or missing, missing o-ring. | 5. Check for damaged/missing filter or cut/missing o-ring. | |
| 6. Valve Body Malfunction. | 6. Inspect valve body for stuck/ sticky regulator valve or shift group valves. | |
| 7. Oil pump gears worn/damaged. | 7. Inspect pump for damage or excessive clearances. Replace if needed. | |
| No Drive or Reverse Engagement (vehicle will not move) | 1. Fluid level low. | 1. Check and adjust fluid level. (Refer to TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE) . |
| 2. Misadjusted/damaged shift cable. | 2. Inspect shift system. Adjust and/or replace worn/damaged parts. | |
| 3. Filter plugged. | 3. Check TC out pressure, if < 10psi, check for plugged filter. Replace if needed. | |
| 4. Filter damaged or missing, missing filter o-ring. | 4. Check for damaged/missing filter or cut/missing o-ring. | |
| 5 Hydraulic system-Low/no line pressure. | 5. Remove valve body. Inspect or sticky/stuck regulator valve. If valve motion is free, replace line pressure solenoid and retest. If condition still exists check for worn/damaged pump. Replace pump assembly if needed. | |
| Shudder garage shift R-D or D-R | 1. Transmission adaptation/ calibration. | 1. Check for latest level TCM software. Perform the TCM adaptation procedure. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCEDURE) |
| 2. Customer applying throttle while shift is in progress. | 2. Instruct customer to wait until shift is complete prior to applying throttle. | |
| Harsh rolling garage shift R-D or D-R | 1. Transmission adaptation/ calibration. | 1. Check for latest level TCM software. Perform the TCM adaptation procedure. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCEDURE) |
| 2. Customer shifting into desired range with vehicle motion. | 2. Instruct customer to only shift into the desired range with the vehicle stopped and the service brake applied. | |
| 3. Transmission in limp-home mode. | 3. Check TCM for DTCs. Repair as needed. | |
| Engine stalls when transmission is shifted into R or D. | 1. Converter clutch or lock up control valve malfunction. | 1. Perform converter clutch diagnostics test. Inspect valve body for stuck or sticky lock up control valve. If valve motion is free, replace lock up solenoid and retest. |
| 2. Defective torque converter. | 2. Replace torque converter. | |
| Clunk/click noise during garage shift from R-D or D-R | 1. Stick-slip condition between output flange and output shaft nut upon torque reversal from R to D or D to R. Click on first launch. | 1. Replace output flange and nut. |
| Harsh Upshift or downshift | 1. Transmission adaptation/ calibration. | 1. Check for latest level TCM software. Perform the TCM adaptation procedure. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCEDURE) |
| 2. Valve body malfunction. | 2. Inspect valve body for sticky/stuck valves. Repair as needed. If valve motion is free, replace shift pressure solenoid and line pressure solenoid and retest. | |
| 3. Damaged or misbuilt clutch. | 3. Remove, disassemble and repair transmission as needed. | |
| EMCC Shudder | 1. Transmission adaptation/ calibration. | 1. Check for latest level TCM software. Perform the TCM adaptation procedure. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCEDURE) |
| 2. Fluid condition, contamination or wrong type. | 2. Change fluid per service procedures. (Refer to TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE) . | |
| 3. Valve body malfunction. | 3. Remove valve body. Inspect for sticky/stuck lock up control valve. If valve motion is free, replace the lock up solenoid and retest. | |
| 4. Defective torque converter. | 4. Replace torque converter. | |
| Grating or Scraping Noise proportional to engine speed | 1. Torque converter bolts contacting dust shield. | 1. Dust shield bent. Replace if needed. Torque converter bolt backed out. Replace with new bolt and torque to proper level. |
| 2. Damaged/broken drive plate. | 2. Inspect driveplate. Replace if needed. | |
| Grating or Scraping Noise proportional to transmission output speed | 1. Driveshaft or rear axle noise. | 1. Check driveshaft, center bearing and axle for noise or contact with other components. |
| 2. Transmission output bearing noise. | 2. Replace output bearing and retest. | |
| 3. Internal transmission damage. | 3. Remove, disassemble and repair transmission as needed. | |
| High pitched whine/noise related to engine speed | 1. Fluid level low. | 1. Check and adjust fluid level. (Refer to TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE) . |
| 2. Transmission in limp-home mode. | 2. Check TCM for DTCs. Repair as needed. | |
| 3. Filter plugged. | 3. Check TC out pressure, if < 10psi, check for plugged filter. Replace if needed. | |
| 4. Filter damaged or missing. | 4. Check for damaged/missing filter or cut/missing o-ring. | |
| 5. Oil pump bushing worn/ damaged. | 5. Visually inspect for worn or damaged pump bushing. Replace pump assembly if needed. | |
| 6. Oil pump gears worn/ damaged. | 6. Inspect for worn or damaged pump gears. Replace pump assembly if needed. | |
| Slips on 1-2 upshift | 1. Transmission adaptation/ calibration. | 1. Check for latest level TCM software. Perform the TCM adaptation procedure. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCEDURE) |
| 2. Fluid level low. | 2. Check and adjust fluid level. (Refer to TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE) . | |
| 3. Filter damaged or missing. | 3. Check for damaged/missing filter or cut/missing o-ring. | |
| 4. Valve body malfunction. | 4. Check for sticky/stuck 2-3 shift pressure valve or regulator valve. | |
| 5. F1 or K1 clutch damaged. | 5. Disassemble transmission inspect for damaged F1 or K1 clutch. Repair as needed. | |
| Slips on 2-3 upshift | 1. Transmission adaptation/ calibration. | 1. Check for latest level TCM software. Perform the TCM adaptation procedure. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCEDURE) |
| 2. Fluid level low. | 2. Check and adjust fluid level. (Refer to TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE) . | |
| 3. Filter damaged or missing. | 3. Check for damaged/missing filter or cut/missing o-ring. | |
| 4. Valve body malfunction. | 4. Check for sticky/stuck 2-3 shift pressure valve or regulator valve. | |
| 5. F2 or B2 clutch damaged. | 5. Disassemble transmission, inspect for damaged F2 or B2 clutch. Repair as needed. | |
| Slips on 3-4 upshift | 1. Transmission adaptation/ calibration. | 1. Check for latest level TCM software. Perform the TCM adaptation procedure. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCEDURE) |
| 2. Fluid level low. | 2. Check and adjust fluid level. (Refer to TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE) . | |
| 3. Filter damaged or missing. | 3. Check for damaged/missing filter or cut/missing o-ring. | |
| 4. Valve body malfunction. | 4. Check for sticky/stuck 2-3 shift pressure valve or regulator valve. | |
| 5. K3 or B2 clutch damaged. | 5. Disassemble transmission, inspect for damaged K3 or B2 clutch. Repair as needed. | |
| Slips on 4-5 upshift | 1. Transmission adaptation/ calibration. | 1. Check for latest level TCM software. Perform the TCM adaptation procedure. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - STANDARD PROCEDURE) |
| 2. Fluid level low. | 2. Check and adjust fluid level. (Refer to TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE) . | |
| 3. Filter damaged or missing. | 3. Check for damaged/missing filter or cut/missing o-ring. | |
| 4. Valve body malfunction. | 4. Check for sticky/stuck 2-3 shift pressure valve or regulator valve. | |
| 5. B1 or K1 clutch damaged. | 5. Disassemble transmission, inspect for damaged B1 or K1 clutch. Repair as needed. | |
| In-gear shudder on heavy acceleration | 1. Fluid level low. | 1. Check and adjust fluid level. (Refer to TRANSMISSION/AUTOMATIC - NAG1/FILTER - STANDARD PROCEDURE) . |
| 2. Filter damaged or missing. | 2. Check for damaged/missing filter or cut/missing o-ring. | |
| No Drive engagement following a shift to N | 1. Customer shifting into N at vehicle speeds greater than 25mph and tipping in on the throttle. | 1. Instruct the customer that they should not shift into N at vehicle speeds greater 25mph. |
| 2. Shift system malfunction. | 2. Inspect shift system for proper adjustment or damage. Check shifter for DTCs. Repair as needed. | |
| Reverse gear position blocked engagement when moving shift lever from D position | 1. Customer shifting into R at vehicle speeds greater than 7mph. | 1. Instruct customer that R shifter position is blocked at vehicle speeds greater than 7mph. |
| 2. Shift system malfunction. | 2. Inspect shift system for proper adjustment or damage. Check shifter for DTCs. Repair as needed. | |
| No Engine Cranking in P or N | 1. Gearshift cable adjustment. | 1. Adjust shift cable and retest. |
| 2. Shift system malfunction. | 2. Check shifter DTCs. Inspect shift cable and lever assembly. Adjust and/or replace worn/ damaged parts. | |
| 3. Valve body malfunction. | 3. Starter lockout contact malfunction. Remove valve body, replace lead frame assembly. | |
| Fluid Leak | 1. Leak in area of bell housing. | 1. Check bolt torque on internal bell housing bolts. If loose, replace fastener and torque to proper level. If bolts are to proper torque level, check pump outer seal and impeller seal. Replace if needed. |
| 2. Leak in area of control unit (valve body) electrical connector. | 2. Check connector for damaged (cut) or missing o-rings. Replace as needed. | |
| 3. Leak in area of pan gasket. | 3. Check for proper torque on oil pan clamps. Check for mis-positioned or rolled gasket. Repair as needed. | |
| 4. Free Wheeling Clutch F2 Defective. | 4. Replace Free Wheeling Clutch F2, Hollow Shaft, and Rear Sun Gear/Inner Disc Carrier K3. | |
| 5. Leak in area of park guide plug. | 5. Remove park guide plug. Check for damaged (cut) or missing o-ring. If o-ring is in good condition, install new plug. | |
| 6. Leak in area of shift lever. | 6. Check for damaged shift lever seal or damaged lever. Repair as needed. | |
| 7. Leak in area of output flange. | 7. Check for worn/damaged slinger seal and output seal. Visually inspect output flange seal surface for damage. Repair as needed. | |
| 8. Leak in area of transmission vent. | 8. Check fluid level for overfill condition. Adjust as needed. If fluid level is within specification, ride check vehicle. Monitor transmission temperature. If high operating temperatures are observed, fluid may be contaminated or cooling system malfunctioning. Change fluid per service procedures. Refer to cooling system diagnostics if needed. | |
| 9. Leak in area of transmission fill tube. | 9. Inspect fill tube cap for proper installation. Inspect fill tube grommet between case and fill tube for leakage. Repair as needed. |