Initial Inspection and Diagnostic Overview
Specifications
AW 50-42 TCM AUTOMATIC TRANSMISSION
* Refer to description "Design and Function, Control Module".
Transmission Identification
Ratios:/Capacity:
Resistance for components
The resistance values stated below are at +/-20°C (+68°F) unless otherwise indicated.
Line pressure (MPa) at idling speed (rpm)
Stall speed (rpm), Line pressure (Mpa)
Stall speed at sea level and ambient air temperature of 20°C (68°F.) Speed decreases by 120 rpm per 1000 meters (3,300 feet) above sea level and 50-100 rpm per 10°C (50°F) above +20°C (68°F) ambient air temperature.
TRANSMISSION SHIFT SPEEDS, km/h (mph)
The AW 50-42 automatic transmission is equipped with a 'mode selector" with three different driving modes: Economy, Sport and Winter. Depending on the selected mode, shift speeds are determined and mechanical lock-up engaged at different speeds. Below are the shift speeds for the three driving modes together with the engine types and model years at selected throttle openings. Set gearshift selector to position D. When test driving, the speeds in the tables should be used as a guide since it is not possible to take an exact reading of speed and throttle position during actual driving.
Economy Mode (E), D position 1992-1993
Economy Mode (E), D position 1994-1995
Sport Mode (S), D position 1992-1993
Sport Mode (S), D position 1994-1995
Winter Mode (W), D position 1992-1993
Winter Mode (W), D position 1994-1995
MECHANICAL LOCK-UP
Like shift speeds, mechanical lock-up of the torque converter at different speeds is engaged depending on the driving mode and gear position (D, 3, L) selected at the time. In addition to road speed, the transmission temperature and the engine load (throttle opening) are factors. Lock-up is engaged at a lowest oil temperature of 20°C = 68°F. Mechanical lock-up also occurs in 2nd, 3rd and 4th gears. The tables show lock-up engagement and release for gears and types of engine in position D. When test driving,the speeds in the tables should be used as a guide since it is not possible to take an exact reading of speed and throttle position during actual driving.
Economy Mode (E), D position 1992-1993
Economy Mode (E), D position 1994-1995
Sport Mode (S), D position 1992-1993
Sport Mode (S), D position 1994-1995
Winter Mode (W), D position 1992-1993
Winter Mode (W), D position 1994-1995
INSTALLATION OF FASTENERS
General Requirements
Clean all surfaces in the fastener, first mechanically and then with a grease solvent. If necessary, replace screws and nuts for torque-installed fasteners.
NOTE: Lock nuts must always be replaced with new ones. If re-using screws and nuts, always clean and grease properly first.
NOTE: Always replace screws, or screws and nuts for torque/protractor-installed fasteners. Does not apply to M22 self-locking drive shaft nuts.
Values below are accurate to within +/- 5%. 1 Nm = 0,1 kpm (0.74 ft.lbs)
Tightening wheel studs
When installing and tightening wheel studs the following applies. Ensure that the brake disk and wheel rim mating surfaces are clean. Grease the hub center location dowel for the rim. Use rust inhibitor 1161030-0.
Tighten the studs lightly. Finally, tighten nuts diagonally to 110 Nm (81 ft. lbs). Torque socket 1158147-7 must be used when tightening with a nut driver.
Diagonal tightening and torque application is important to prevent tension in the brake disc.
NOTE: The torque socket wrench is designed for tightening wheel studs with normal, hammer, pneumatic tighteners with a torque capability of 250-350 Nm (185-260 ft. lbs).
Rust inhibitor, grease etc.:
