Service Information: Description: Notes

1 - TORQUE CONVERTER	11 - PARKING LOCK GEAR
2 - OIL PUMP	12 - INTERMEDIATE SHAFT
3 - DRIVESHAFT	13 - FREEWHEEL F2
4 - MULTI-DISC HOLDING CLUTCH B1	14 - REAR PLANETARY GEAR SET
5 - DRIVING CLUTCH K1	15 - CENTER PLANETARY GEAR SET
6 - DRIVING CLUTCH K2	16 - ELECTROHYDRAULIC CONTROL UNIT
7 - MULTI-DISC HOLDING CLUTCH B3	17 - FRONT PLANETARY GEAR SET
8 - DRIVING CLUTCH K3	18 - FREEWHEEL F1
9 - MULTI-DISC HOLDING CLUTCH B2	19 - STATOR SHAFT
10 - OUTPUT SHAFT	20 - TORQUE CONVERTER LOCK-UP CLUTCH

The NAG1 automatic transmission is an electronically controlled 5-speed transmission with a lock-up clutch in the torque converter. The ratios for the gear stages are obtained by 3 planetary gear sets. Fifth gear is designed as an overdrive with a high-speed ratio. See Fig 1.

NAG1 identifies a family of transmissions and means "N"ew "A"utomatic "G"earbox, generation 1. Various marketing names are associated with the NAG1 family of transmissions, depending on the transmission variation being used in a specific vehicle. Some examples of the marketing names are: W5A300, W5A380, and W5A580. The marketing name can be interpreted as follows:

1. W = A transmission using a hydraulic torque converter.
2. 5 = 5 forward gears.
3. A = Automatic Transmission.
4. 580 = Maximum input torque capacity in Newton meters.

The gears are actuated electronically/hydraulically. The gears are shifted by means of an appropriate combination of three multi-disc holding clutches, three multi-disc driving clutches, and two freewheeling clutches.

Electronic transmission control enables precise adaptation of pressures to the respective operating conditions and to the engine output during the shift phase which results in a significant improvement in shift quality.

Furthermore, it offers the advantage of a flexible adaptation to various vehicle and engines.

Basically, the automatic transmission with electronic control offers the following advantages:

1. Reduces fuel consumption.
2. Improved shift comfort.
3. More favorable step-up through the five gears.
4. Increased service life and reliability.
5. Lower maintenance costs.