BMW 3 Series E30

since 1983-1994 release

Repair and operation of the car



BMW E30
+ 1. Maintenance instruction
+ 2. Maintenance
+ 3. Engine
+ 4. Cooling system
+ 5. Heating and ventilation
+ 6. Fuel system
+ 7. Exhaust system
- 8. Transmissions
   + 8.1.2. Specifications
   - 8.2. Automatic transmission
      8.2.2. Specifications
      8.2.3. Diagnostics of automatic transmission
      8.2.4. Draft of the selector of transmission
      8.2.5. kick cable - down - the mode
      8.2.6. The blocking backing signal switch/switch
      8.2.7. Removal and installation of transmission
      8.2.8. Epiploons of automatic transmission
      8.2.9. "Automatic machine"
+ 9. Coupling
+ 10. Brake system
+ 11. Running gear
+ 12. Body
+ 13. Electric equipment
+ 14. Useful tips
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8.2.9. "Automatic machine"

GENERAL INFORMATION

Everything that will be required to you, is to study position of the lever selector of management of transmission and its main positions:

P-parking (parking brake);

R-reverse (backing);

N-neutral;

D-advance.

So, you start the engine, put the lever in position D – and went... Until you arrive to the place and do not switch off the engine. The car in process of pressing a pedal of "gas" itself will start, switch transfers, to disperse, stop.

Of course, even cleverest "automatic machine" cannot "guess" that it will come to your mind in one or two seconds. It works as if with delay: on a mechanical box you would already switch transfer, having prepared, for example, for overtaking, and "automatic machine" will switch transfer only while you press "gas" and will begin overtaking. Therefore on all "automatic machines" additional functions are entered: position of the lever selector and (if transmission has electronic control) switch of programs.

Let's consider appointment and functions of these additional devices on the example of BMW 750.

P-R-N-already it is clear. The following position – D. In this position of the lever selector the on-board computer, receiving a signal from the sensor of provision of a pedal of supply of fuel and from the car speed sensor, switches transfers – from the first (lowest) of to fourth (accelerating). Braking by the engine when dumping "gas" does not happen. But what to do if it is necessary, for example, on the slippery road or on descent?

Actions simple – forcibly include the transfers necessary to you corresponding to provisions of the lever selector 3 - 2 – 1: having dumped "gas" and having switched the lever on 3, you will feel noticeable braking by the engine in the range from 100 (at higher speed it is not necessary to use) to 40 km/h. Further, having switched on 2, it is possible to be braked about 15–20 km/h, and having included 1, you will move to a full stop. It is recommended on the good free road in advance to be trained and learn to brake the engine to feel efficiency of such actions as they considerably differ from "mechanics" habitual to us.

The switch of programs has three provisions: S-the sports mode, E – economic, M – manual. In the manual mode position of the lever selector corresponds to the included transfer. Thus, you have an opportunity to operate transmission as semi-automatic. It is convenient at the movement on the slippery road, sand, on dirt i.e. where sharp changes of force on a wheel are inadmissible.

The sports mode differs from economic only in the fact that gear shiftings happen at big turns of the engine.

At cars of other firms the lever selector can be issued differently, but functions and ways the same managements. So, on modern American and Japanese cars after a neutral there is a mode D that means overdrive (O.D.) also corresponds to the fourth, overdrive gear. Sometimes on the lever selector there are only positions forward (D, 2 and 1) and there is a button of inclusion shutdown of an overdrive (JEEP Grand Cherokee, LINCOLN Mark VIII, etc.). In this case for switching off of the fourth transfer it is necessary to turn on the button in situation "O.D.off".

It is necessary to pay attention that on many American FORD cars (Taurus, Escort, Town Car) lever selector has O.D positions., D and 1, i.e. it is impossible to include forcibly the second transfer that limits a possibility of braking to the engine and the movements on rises.

Owners of cars with automatic transmission need to follow several rules:

Check oil level in a box at least two times a month.

At the same time it is necessary to remember that:

 – level of oil is checked only at the working engine;
 – on the probe usually there are tags both for cold oil, and for hot. If in a tag temperature at which it is necessary to check oil level is not designated, do it only on a heated-up box – after 10–15 km of a run;
 – oil level is checked, as a rule, on a parking (P). On the probe surely there is an inscription specifying a way of check. So, on JEEP Grand Cherokee the level of oil is checked only for neutral.

You make replacement of oil in a box through 30 000 km of a run.

At the same time it is necessary to consider that universal oil for automatic transmissions – Dextron. Modern oil is designated by Dextron III. It can be mixed with oils of the previous brands (Dextron II, IID and IIE). It has stabler vyaznost and more powerful additives improving work of a box. In transmissions of production CHRYSLER MOPAR ATF Plus oil which with success can be replaced with Dextron III is used. For transmissions of production of ZF also use oil like Dextron, however on the BMWs 540 and 740 cars only synthetic ESSO ATF LT 71141 oil is used. It is used in all transmissions of this firm having the green company label. It is possible to mix oils if necessary, but it is undesirable.

Tow the car with an automatic box not further of 30 km and with a speed no more than 50 km/h in case the engine is faulty or in a box there is no oil.

Remember that at emergency it is possible to tow the car on a long distance, but it is necessary to fill in in the transmission in addition 2–3 l of oil that all details literally bathed in it.

Avoid an engine overheat as it can lead to a sharp overheat of oil in a box and, as a result, to failure of a box.

And the last: at emergence of noise, vibration, rigid pushes at gear shifting, tightened switchings etc. immediately address to the specialized centers for repair of automatic transmissions, especially in the presence in your car of electronically controlled transmission. Timely diagnostics will prevent considerable costs of repair.

Do not try to eliminate independently malfunction – your curiosity, self-confidence and economy on "kulibiny" will cost very much.