Dodge Nitro. Manual — part 351

Fig. 275: Identifying Torque Converter Components
Courtesy of CHRYSLER LLC

1 - TURBINE
2 - IMPELLER
3 - STATOR
4 - INPUT SHAFT
5 - STATOR SHAFT
6 - PISTON
7 - COVER SHELL

2007 Dodge Nitro R/T

2007 AUTOMATIC TRANSMISSION NAG1 - Service Information - Nitro

In a standard torque converter, the impeller (2) and turbine (1) are rotating at about the same speed and the
stator (3) is freewheeling, providing no torque multiplication. By applying the turbine's piston and friction
material (9), a total converter engagement can be obtained. The result of this engagement is a direct 1:1
mechanical link between the engine and the transmission. See Fig. 275.

The clutch can be engaged in second, third, fourth, and fifth gear ranges.

The TCM controls the torque converter by way of internal logic software. The programming of the software
provides the TCM with control over the torque converter solenoid. There are four output logic states that can be
applied as follows:

No EMCC

Partial EMCC

Full EMCC

Gradual-to-no EMCC

NO EMCC

Under No EMCC conditions, the TCC Solenoid is OFF. There are several conditions that can result in NO
EMCC operations. No EMCC can be initiated due to a fault in the transmission or because the TCM does not
see the need for EMCC under current driving conditions.

PARTIAL EMCC

Partial EMCC operation modulates the TCC Solenoid (duty cycle) to obtain partial torque converter clutch
application. Partial EMCC operation is maintained until Full EMCC is called for and actuated. During Partial
EMCC some slip does occur. Partial EMCC will usually occur at low speeds, low load and light throttle
situations.

FULL EMCC

During Full EMCC operation, the TCM increases the TCC Solenoid duty cycle to full ON after Partial EMCC
control brings the engine speed within the desired slip range of transmission input speed relative to engine
RPM.

GRADUAL-TO-NO EMCC

This operation is to soften the change from Full or Partial EMCC to No EMCC. This is done at mid-throttle by
decreasing the TCC Solenoid duty cycle.

REMOVAL

8 - INTERNALLY TOOTHED DISC CARRIER
9 - CLUTCH PLATE SET
10 - EXTERNALLY TOOTHED DISC CARRIER
11 - TURBINE DAMPER

2007 Dodge Nitro R/T

2007 AUTOMATIC TRANSMISSION NAG1 - Service Information - Nitro

TORQUE CONVERTER

1. Remove transmission and torque converter from vehicle. See REMOVAL.

2. Place a suitable drain pan under the converter housing end of the transmission.

3. Pull the torque converter forward until the center hub clears the oil pump seal.

4. Separate the torque converter from the transmission.

INSTALLATION

TORQUE CONVERTER

Fig. 276: Measuring Torque Converter Installation Depth
Courtesy of CHRYSLER LLC

CAUTION: Verify that transmission is secure on the lifting device or work

surface, the center of gravity of the transmission will shift when the
torque converter is removed creating an unstable condition. The
torque converter is a heavy unit. Use caution when separating the
torque converter from the transmission.

1 - TORQUE CONVERTER

2007 Dodge Nitro R/T

2007 AUTOMATIC TRANSMISSION NAG1 - Service Information - Nitro

Check converter hub and drive flats for sharp edges, burrs, scratches, or nicks. Polish the hub and flats with
320/400 grit paper or crocus cloth if necessary. The hub must be smooth to avoid damaging the pump seal at
installation.

1. Lubricate oil pump seal lip with transmission fluid.

2. Place torque converter in position on transmission.

3. Align torque converter to oil pump seal opening.

4. Insert torque converter hub into oil pump.

5. While pushing torque converter inward, rotate converter until converter is fully seated in the oil pump

gears.

6. Check converter seating with a scale and straightedge. See Fig. 276. Surface of converter lugs should be

at least 19 mm (3/4 in.) to rear of straightedge when converter is fully seated.

7. If necessary, temporarily secure converter with C-clamp attached to the converter housing.

8. Install the transmission in the vehicle.

9. Fill the transmission with the recommended fluid.

2 - TRANSMISSION HOUSING

CAUTION: Do not damage oil pump seal or converter hub while inserting torque

converter into the front of the transmission.

2007 Dodge Nitro R/T

2007 AUTOMATIC TRANSMISSION NAG1 - Service Information - Nitro