Detailed technical specifications (BMW 3 Series E21)

Automatic planetary three-speed gearbox type 3 HP 22 with torque converter manufactured by ZF.

The selector lever has six positions: P - parking; R — reverse; 0 or N - neutral; A or D - automatic engagement of I, II and III gears; 2 - automatic engagement of I and II gears; 1 — only 1st gear is engaged.

The engine can only be started if the selector lever is in position 0 or N or P.

In positions A, D and 2 of the selector lever, a lower gear is automatically engaged, and when the accelerator pedal is pressed all the way down, a lower gear is forced into engagement (kick-down).

The front oil pump of the automatic transmission, which supplies oil to the torque converter, locking mechanism and clutches, is driven by 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 off. Therefore, a faulty vehicle can only be towed by setting the selector lever to position 0 or N at a speed of no more than 50 km/h for a distance of no more than 50 km or by disconnecting the cardan shaft from the gearbox.

Automatic transmission markings

Automatic transmission gear ratios

Torque converter

Data for verification

Engine crankshaft speed with the service and parking brakes locked in position "A" ("O") or "2" or "1" or "R" of the selector lever, rpm:

• "318": 2000±50;
• "320" with 4-cylinder engine: 2100±50;
• "320" with 6-cylinder engine: 2270;
• "323": 2060.

To check, perform the following operations: brake the car with the parking brake; start the engine and let it idle until the gearbox oil temperature reaches 50-80°C; place the selector lever in one of the above positions; press the brake pedal; press the accelerator pedal smoothly; after the engine speed stops increasing, read the tachometer and release the accelerator pedal; place the selector lever in neutral position and repeat the above operations at other lever positions.

Warning: When checking, press the accelerator pedal for no more than 3-5 seconds. After each stage of the check, let the engine run for some time at idle speed.

Working pressure

* The numerator shows the values for the "320" with a 6-cylinder engine, the denominator shows the values for the "323i".

Gear shift moments

Low gear engagement speeds

* At crankshaft speed of 3500-4000 rpm.


** At crankshaft speed of 2800-1450 rpm

Data for adjustment

Distance between hydraulic block and plunger of pressure reducing valve, mm: 11.5.

Gearbox oil

Gearbox filling capacity, l:

• total capacity: 6.05;
• at 1st filling: about 2.2;
• when changing oil: about 2.0.

Oil used: ATF Dexron II.

Replacement frequency: every 30,000 km.

The difference in the amount of oil between the "maxi" and "mini" marks on the oil dipstick, l: about 0.4.

Tightening torques of main threaded connections, kgf·m

• Automatic transmission mounting bolt to engine block: M8: 2.2—2.4; M10: 4.3 - 4.8; M12: 8.0-8.8.
• Bolt for fastening the torque converter to the drive disk: 2.5-2.7.
• Threaded plug M18x1.5: 4.1-4.7.
• Nut for fastening the oil filler pipe to the oil pan: 10.2-11.7.
• Oil pan drain plug: 1.5-1.7.
• Bolt for fastening the selector lever bracket to the gearbox: 0.8-1.0.
• Bolt for fastening the flange of the centrifugal regulator to the gearbox housing: 1.5-1.7.
• Bolt for fastening the gearbox extension to the gearbox housing: 2.3-2.6.
• Bolt M6 of centrifugal regulator: 1.0-1.1.
• Front oil pump mounting bolt M6: 1.0-1.1.

(This article is based on information from the website «BMWMAN»)