The selector lever has six positions: «R» - parking; «R» - reverse; «ABOUT» or «N» — neutral; «A» or «ABOUT» — automatic inclusion of I, II and III gears; «2» automatic inclusion of I and II gears; «1» — the inclusion of only 1st gear.
The engine can only be started if the selector lever is in position «ABOUT», «N» or «R».
Under the provisions «A» And «2» of the selector lever, when the car starts off, the 1st gear is automatically engaged, and when the accelerator pedal is pressed all the way, a lower gear is forcibly switched on («kickdown»).
The drive of the front oil pump of automatic transmission, which provides oil supply to the torque converter, the locking mechanism and the clutches, is carried out from the torque converter in accordance with the engine crankshaft speed, i.e. the pump does not rotate when the vehicle is towed with the engine not running. Therefore, a faulty vehicle can only be towed with the selector lever in position «ABOUT» or «N», at a speed of not more than 50 km/h for a distance of not more than 50 km, or by disconnecting the cardan shaft from the gearbox.
Characteristics of automatic gearboxes
* Since 1975, all models have been equipped with an automatic gearbox from ZF, type ZNR 22, the characteristics of which are the same as those of the gearbox type 3HP 20.
Operating pressure at selector lever positions «R», «R» And «N»
Working pressure during clutch operation «A» (see photo) and position «A» selector lever
Pressure in the torque converter, kg/cm2:
- «520»
with accelerator pedal position:
- «idling»: 3,5-4;
- «kickdown»: 5-6;
- «525» And «528»: less than 4 up to engine speed of 1500 rpm.
Reducing valve pressure
Pressure in the centrifugal oil pressure regulator at a speed of 50 km/h, kg/cm2:
- «520»: 1,10-1,30;
- «525», «528»: 1,27-1,35.
Adjustment Data
Shift Moments (at the position «A» selector lever)
Gearbox oil
Change the gearbox oil every 30,000 km. This operation is carried out immediately after the trip, while the oil is warm. Put the selector lever in position «R», stop the engine and drain the oil. Then drain the remaining oil by successively placing the selector lever in all other positions.
Refueling capacity of the gearbox, l:
- at the 1st refueling:
- «520»: ~4,85;
- «525», «528»: ~5.8.
- when changing the oil:
- «520»: ~1,75;
- «525», «528»: ~1.80.
The difference in the amount of oil between the marks «maxi» And «mini» on oil dipstick, l:
- «520»: 0,2;
- «525»: «528»: 0,6.
Oil used: Dexron ATF B 10 128: Dexron ATF B 10 709; Valvomatic ATF, type B, B 10 312.
Tightening torques of the main threaded connections, kgf·m
BMW «520»
- Nuts for fastening the crankcase of an automatic gearbox: 0.5-0.8.
- Hex nut gear sleeve: 1.5.
- Threaded connection of the throttle control cable: 1.5.
- Hex nut for automatic transmission parking lock: 1.0.
- Plug with a diameter of 10 mm in the crankcase of an automatic gearbox: 1.5.
- Bolts of fastening of a case of the hydrotransformer of a torque and the extension of a transmission: 2,3.
- The switch of blocking of a starter and light of a backing: 3,5.
- screw plug (M18) torque converter housing 3.5.
- Oil pump mounting bolt: 1.0.
- Stop bolt of the speedometer drive sleeve: 1.0.
- Pan head bolt (M6) centrifugal pressure regulator: 1.0.
- Nut with collar for fastening the output shaft flange: 10.0-12.0.
- Pressure regulator mounting bolt: 0.8.
- Bolt of fastening of an oil crankcase: 1,0.
- Drain plug: 3.5.
BMW «525», «528»
- Bolt (M6) fastening the hollow shaft to the torque converter housing: 1.0.
- Bolt (M6) fastening the pump to the crankcase torque converter torque: 1.0.
- Nut of a hairpin of fastening of a crankcase of an automatic gearbox: 0.5-0.6.
- screw (M8) attaching the torque converter housing to the gearbox housing 2.2-2.5.
- Nut with shoulder of the output shaft: 10.0-12.0.
- Oil sump bolt: 0.8-0.9.
- Bolt for fastening the throttle control cable bracket to the automatic gearbox housing: 1.5-2.5.
- The union of fastening of a tube of an oil pipeline to a case of the hydrotransformer: 4,0-4,5.
- screw plug (M18) torque converter housing: 3.5-3.9.
- screw plug (M24) torque converter housing: 6.0-6.7.
- screw plug (M10) torque converter housing: 1.5-1.7.
- Bolt (M10) fastening of the leading flange of the torque converter: 4.3-4.8.
- Bolt (M8) fastening the automatic gearbox to the engine block: 2.2-2.4.
Since the 1977 model year, some characteristics of the automatic transmission ZF type 3HP 20, installed on the models «525A» And «528A».
Characteristics of automatic transmission
Pressure test data
Shift Moments
Downshift speeds when shifting the selector lever, km/h:
- out of position «A» and the position «2»: 130;
- out of position «2» into position «1»: 79.
Since the 1978 model year, some characteristics of the ZF ZNR 22 automatic transmission have been changed. Installed on BMW «525A», «528A» And «528iA».
Characteristics of automatic gearbox ZF 3HP 22
Operating pressure
Shift Moments (at the position «D» selector lever)
Downshift speeds (at the position «R» selector lever)
Adjustment Data
Tightening torques of the main threaded connections, kgf·m
- Bolt for fastening the automatic gearbox to the engine block: M8: 2.5-2.7; M10: 4.7-5.1.
- Bolt for securing the gearbox extension to the gearbox housing: 2.3-2.5.
- Oil sump bolt: 0.8-0.9.
- Oil sump drain plug: 3.5-3.9.
- Threaded plug M 18x1.5: 4.0-4.5.
- Nut with collar for fastening the output shaft flange: 10.0-12.0.
- Torque converter mounting bolt to drive flange: M10x16: 4.7-5.1.
Automatic transmission brand Borg Warner type «65»
In the variant version on BMW «528A» installed automatic three-speed planetary gearbox brand Borg Warner type «65» with torque converter. Marking: 032F.
Gear ratios:
- 1st gear: 2.39;
- II gear: 1.45;
- III gear: 1.00;
- reverse: 2.09.
Gear ratio of the speedometer drive: 2.50.
Torque converter type: SS 11.
Torque converter diameter, mm: 280.
Permissible unbalance of the torque converter, gf cm: 46.
Non-flatness of the welded lugs of the torque converter fastening, not more than, mm: 0.254.
Operating pressure with throttle control cable disconnected, kg/cm2:
- at the position «full throttle» accelerator pedals: 3.5-4.6;
- at the position «kickdown» accelerator pedals: 1.4-1.9.
Adjustment Data
Radial clearance between gear and pump housing, mm: 0.023.
Maximum axial clearance between gears and pump housing, no more than, mm: 0.054.
Shift Moments (at the position «A» selector lever)
From model year 1980 on models «518A», «520A», «525A» «528iA» an automatic gearbox ZF 3HP 22 was installed.
Characteristics of automatic gearbox ZF 3HP 22
Operating pressure
Adjustment Data
Distance between hydraulic control unit and pressure reducing valve plunger, mm: 11.5.
Shift Moments (at the position «D» selector lever)
Downshift speeds (at the position «D» selector lever)
Since the 1981 model year, some characteristics of the ZF ZNR 22 automatic gearbox installed on the model have been changed «525A». Marking on the crankcase cover: 170.
Letter marking: RK.
Torque converter marking: W.
Since the 1982 model year, some characteristics of the automatic gearbox ZF 3HP 22 have been changed, which was installed only on models «520iA», «525iA» And «528iA». These changes concerned mainly the KP model «525iA».
Marking on the crankcase cover:
- «520iA»: 232;
- «525iA»: 171;
- «528iA»: 184.
Letter marking of gearbox and torque converter:
- «520iA»: RC and R;
- «525iA»: RY and C1;
- «528iA»: PZ and D1.
Features of the BMW gearbox «525iA»
Gearshift speeds (at the position «D» selector lever)
Downshift speeds
Tightening torques of the main threaded connections, kgf·m
- Bolt for fastening the automatic gearbox to the engine block: M12: 7.8-8.6; M10: 4.7-5.1; M8 2.2-2.7.
- Bolt of fastening of a case of the hydrotransformer of a torque: 2,3-2,6.
- Oil sump drain plug: 1.5-1.7.
- Nut for fastening the oil filler tube to the oil sump: 10.0-11.5.
- Speedometer drive bushing: 1.0-1.1.
- Nut with collar for fastening the output shaft flange: 10.0-11.5.
- Bolt for fastening the torque converter to the drive disk: M8: 4.7-5.0.