TORQUE CONVERTER SERVICE
The torque converter should be replaced under any of the following conditions
- External leaks in the hub weld area.
- Converter hub is scored or damaged.
- Converter pilot is broken, damaged or fits poorly into crankshaft.
- Steel particles are found after flushing the cooler and cooler lines.
- Pump is damaged or steel particles are found in the converter.
- Vehicle has TCC shudder and/or no TCC apply. Replace only after all hydraulic and electrical diagnoses have been made. (Converter clutch material may be glazed.)
- Converter is contaminated with engine coolant containing antifreeze.
- Internal failure of stator roller clutch.
- Heavy clutch debris due to overheating (blue converter).
- Steel particles or clutch lining material found in fluid filter or on magnet when no internal parts in unit are worn or damaged-indicates that lining material came from converter.
- The torque converter should not be replaced if
- The fluid has an odor, is discolored, and there is no evidence of metal or clutch facing particles.
- The threads in one or more of the converter bolt holes are damaged.
- Transaxle failure did not display evidence of damaged or worn internal parts, steel particles or clutch plate lining material in unit and inside the fluid filter.
- Vehicle has been exposed to high mileage (only). The exception may be where the torque converter clutch dampener plate lining has seen excess wear by vehicles operated in heavy and/or constant traffic, such as taxi, delivery or police use.
Torque Converter Clutch Solenoid Valve Control
The torque converter clutch solenoid valve is controlled by the TCM. The plunger closes the drain circuit during the OFF period, and opens the circuit during the ON period. If the percentage of OFF-time increases in one cycle, the pilot pressure drain time is reduced and pilot pressure remains high.
Scheme 98
The torque converter clutch piston is designed to slip to adjust the ratio of ON-OFF, thereby reducing lock-up shock.
OFF-time INCREASING
Amount of drain DECREASING
Pilot pressure HIGH
Lock-up RELEASING
Scheme 99
Scheme 100
Stall revolution within specifications
- Vehicle does not achieve speed of more than 80 km/h (50 MPH)..... One-way clutch seizure in torque converter housing
| CAUTION | Be careful since automatic fluid temperature increases abnormally. Slippage occurs in 3rd and 4th gears in D position..... High clutch slippage Slippage occurs in 2nd and 4th gear in D position..... Brake band slippage Engine brake does not function in 2nd and 3rd gears in D position, 2nd gear in 2 position, and 1st gear in 1 position. |
Stall revolution less than specifications
Scheme 101
- Poor acceleration during starts..... One-way clutch seizure in torque converter
General Specifications
| Engine | QR25DE | VQ35DE | |
|---|---|---|---|
| Automatic transaxle model | RE4F04B | ||
| Automatic transaxle assembly | Model code number | 85X21 | 88X02 |
| Transaxle gear ratio | 1st | 2.785 | |
| 2nd | 1.545 | ||
| 3rd | 1.000 | ||
| 4th | 0.694 | ||
| Reverse | 2.272 | ||
| Final drive | 4.087 | 3.789 | |
| Recommended fluid | Nissan Matic "D" (Continental U.S. and Alaska) or Canada Nissan Automatic Transmission Fluid (1) | ||
| Fluid capacity l (US qt, lmp qt) | 9.2 (9.75, 8.125) | ||
| (1) Refer to SERVICING - A/T article. | |||
| (1) | Refer to SERVICING - A/T article. |
General Specifications
Scheme 102
Scheme 103
Note. Lock-up vehicle speed indicates the speed in D 4 position. Perform lock-up inspection after warming up engine. Lock-up vehicle speed may vary depending on the driving conditions and circumstances.
Scheme 104
Scheme 105
Scheme 106
Note. Lock-up vehicle speed indicates the speed in D 4 position. Perform lock-up inspection after warming up engine. Lock-up vehicle speed may vary depending on the driving conditions and circumstances.
