All owners of cars with automatic transmission, it is necessary to monitor not only the condition of the oil in the box, but also its level.

Quantity check procedure transmission oil significantly differs from the same mechanics, and has its own characteristics.

Let's consider why checking the oil level in an automatic transmission, or rather ATF fluid, is so important and why its amount can change. By what symptoms can one understand that the level is higher or lower than the norm, what consequences this can lead to, and how to correctly measure.

A lack of fluid in an automatic box may occur after a long period of operation, due to leaks and ATF evaporation. If the leak occurs quickly enough, such as when a pallet is punctured, the vehicle will refuse to drive almost immediately. Much more dangerous is a small flaw, it will kill the box slowly and unnoticed by the owner.

Symptoms

• Slipping and low gears when driving, especially on a lift, when the pump begins to take air from the sump instead of oil.
• Jerks when changing gears.
• The howl of the box and the change in the sound of work at different speeds.

Effects

Low level oil violates the temperature regime of its operation - a smaller amount heats up much faster, the liquid begins to "burn".

The pump will draw air along with the oil, resulting in an air-oil emulsion, which is a compressible liquid. The torque converter in the automatic transmission works precisely due to the pressure of the liquid, and a change in its characteristics will affect the correct operation of this unit, and the entire box as a whole.

The ATF resource will decrease, it will have to be changed much faster.

The lubrication of the gearbox parts and the heat sink will worsen, as a result, the resource of the automatic transmission itself will decrease.

High ATF level

The main reason for the high oil level is just incorrect measurements, after which the car owner begins to add fluid to the box on his own.

When replacing a workshop, workers can also fill in too much. The reason is simple: the hot liquid is drained, the cold one is poured, and the hot ATF has a much larger volume. This means that the cold one will subsequently expand even more.

Symptoms

You can determine that the oil level is higher than normal by the following signs.

• The box starts to dull, kick, the gears may not turn on.
• ATF leaks in the area of \u200b\u200bthe breather, dipstick, oil seals. It is no coincidence that it has a red color, which distinguishes it from all other process fluids.
• Foam on the dipstick. Moreover, it is not just the presence of bubbles, but a stable foamed liquid.

Effects

The clutch discs begin to slip relative to each other, and this leads to their combustion and increased wear.

The consequences of overfilling are practically the same as for underfilling. The liquid begins to reach the rotating parts of the box and foams, forming an emulsion. Only in addition to compressibility and poor heat transfer, you also get a serious increase in the volume of ATF, the excess of which will be thrown out through the breather of the automatic transmission ventilation system.

How to check the oil level correctly

Probe box

It is because of the enormous importance of the amount of ATF in the machine, it is important to be able to correctly measure it.

If the technical documentation for the car does not clearly indicate the method of checking, use the generally accepted rules for all automatic transmissions.

1. The measurement is carried out on a transmission warmed up to operating temperature. It is important to warm up the box and the liquid in it, and not the engine. It is difficult to do this at idle speed, you need to drive at least 10-15 kilometers.
2. The measurements are taken with the engine running. Only in this case, the fluid circulates throughout the system, and does not stand idle in the crankcase.
3. The selector lever is in the P (parking) position. In this position, the radiator valve opens and the fluid is circulated in full.

After you have warmed up the car, it must be placed on a flat, horizontal surface, the automatic transmission must be switched to P mode. Take out the dipstick and wipe it dry, reinsert it all the way and remove it to see the oil level.

You can download a list of manufacturers and vehicles with automatic transmission and determine which gearbox you have.

Most often, you can see the inscriptions COLD (cold) and HOT (hot) on the probe, some immediately indicate the temperature. They also have notches or marks indicating the permissible oil level range. There are always several values, and the reason is that aTF fluids a sufficiently high level of thermal expansion. This means that the volume of oil in an automatic transmission is highly dependent on its temperature.

If, when checking the oil level, the ambient temperature differs from +20 (sometimes the temperature is indicated on the dipstick), the COLD value reading may be incorrect. Many owners of automatic transmissions complain that the fluid level does not reach even the minimum COLD risk on the dipstick. This is quite possible if checks are made for cold, at zero, or negative ambient temperatures.

If measurements show that there is not enough fluid, add a small amount and check the oil level in the box again.

If the values \u200b\u200bexceed the permissible values, remove the excess ATF through the filler neck. The easiest way to do this is with homemade device... It is necessary to put a piece of the dropper tube on the syringe and pump out the excess. After that also carry out a control check.

Feelerless automatic transmission

And how to check the oil level in the automatic transmission if there is no dipstick on it? For example, DP0 / AL4 boxes, for Peugeot, Renault, Citroen with engines up to 2 liters. Each of them must have a control plug, it can be located anywhere: on the pallet, in the body, in the crankcase wall. In some cars, it is also a filler (ZF boxes on BMW), oil is poured into them until it starts to flow back.

When operating a car, every owner must be able to correctly check the oil level in the automatic transmission. Checking the oil level in an automatic box is a mandatory element that ensures the normal operation of the unit. Too low or too high an automatic transmission oil level can lead to serious malfunctions. How to check the oil level in the automatic transmission, we will consider in this article.

The need to check the lubricant level in the automatic transmission

If the level of the amount of oil in the automatic transmission changes, then this can lead to negative consequences. Lack of oil solution can lead to the following consequences:

1. Increased wear of rubbing surfaces of parts and their rapid failure.
2. High working temperature gearbox parts.
3. Increase in solution and loss of oil of its technical characteristics.
4. The possibility of air entering the oil solution, as a result of which it turns into an air-oil mixture. This will reduce the quality of lubrication of components and assemblies and lead to overheating.
5. Late gear changes and a general reduction in the resource of the automatic transmission.

If the measurement of the oil solution showed that it is above the norm, then this can also entail an unpleasant consequence. It can manifest itself in the following:

1. Foaming of the oil solution and an increase in internal pressure inside the gearbox.
2. Due to an increase in internal pressure in the box, it is possible that the oil liquid escapes through the breather or the seals and sealing elements are destroyed.
3. Increased consumption and loss of performance characteristics of the oil solution.

If there is an excess of oil in the gearbox, it must be drained to the specified level. If there is not enough solution, add the required amount. After completing the work, it is recommended to re-check the oil level in the automatic transmission.

Ways to check the lubricant level

There are two options for how to correctly check the oil level in the automatic transmission. You can correctly measure the level with or without a dipstick. These methods differ from each other. Therefore, step by step we will measure the oil level in each of the ways.

Determining the amount of grease using a dipstick

To complete the work, you must:

1. Choose a level area on which to place the vehicle. Warm up the car for 10-15 minutes to a temperature of at least 80 ° C. If desired, you can drive about 5-10 kilometers by car and bring the oil temperature to working condition. After running in, the car must be parked on a level surface.
2. When idle, a decrease in engine speed on the tachometer will be an additional clue that the oil is hot.
3. With the engine running, put the car on the handbrake and depress the brake pedal.
4. Use the gear shift knob to go through all the positions of the wings. In this case, all cavities that the gearbox has are filled. If the car was in motion before measuring the oil liquid, then this procedure can be omitted.
5. Without turning off the engine and without removing the car from the hand brake, the rocker handle must be set to the N - neutral position. After that, you need to wait 2-3 minutes for the liquid to take its natural position, and you can move to the hood.
6. Open the hood, wipe the area around the transmission filler neck.
7. Remove the dipstick from its original place, wipe it with a clean cloth and reinstall it in its original place.
8. Remove the dipstick again and inspect the reference marks. The solution value can be measured according to the inscriptions HOT (hot) and COL (cold). Each inscription has a top and bottom mark. The correct indicator for the fluid level with a warm engine should be located between the upper and lower marks of the inscription HOT.
9. Checking the amount of oil when the engine is cold is not recommended, since there is a high error in checking.

The solution is topped up in the hole into which the measuring rod is inserted. For this, an ordinary funnel with a filter and a clean cloth are used. Excess fluid is pumped out using a syringe to which a tube from a dropper is connected.

Determination of the amount of grease without a dipstick

How can you check the oil in the automatic transmission if the measuring rod is missing or not provided by the design? These boxes are equipped with an overflow system that allows you to measure the amount of oil. This was the first time such a system was introduced in Ford vehicles. It includes a check plug and a drain (or drain) tube. Height inserted in inspection hole tube allows you to understand to what level the internal volume of the gearbox is filled. If there is a lot of oil, it will start flowing through the tube. If not enough, then there will be no leak. Older cars with automatic transmission can be effectively checked for the presence of oil, but this creates some discomfort when servicing the vehicle.

Measure the volume of oil in such vehicles necessary in the following sequence:

1. Warm up the car for 10-15 minutes to a temperature of at least 80 ° C. If desired, you can drive a car for about 5-10 kilometers and bring the temperature of the lubricant to working condition. After running in or warming up, the car must be installed on an overpass or above a viewing pit.
2. Set the rocker handle to the P - parking position.
3. Open the check nut and insert the drain tube into the hole.
4. Unscrew the filler neck on the gearbox and insert the filler hose into it.
5. If the solution did not leak through the drain pipe, add grease through the filler neck until it flows through the drain pipe.
6. If there is an oil leak through the pipe, you need to stop topping up, close the inspection hole and turn on the engine for 1 minute. After that, turn off the engine.
7. Open the inspection hole, check for oil leaks. If there is no leak, add liquid again through the filler neck.
8. Close inspection hole. Use the gear shift knob to go through all the positions of the wings. This will fill all cavities in the gearbox.
9. Reopen the inspection hole, check for oil leaks. If there is no leak, top up the solution again through the filler neck.
10. Remove the filling hose, close the filling hole.
11. Dismantle the drain pipe, install the check plug.

Checking the quality of the lubricant in the box

The quality of the oil can be determined using color analysis and by touch. The presence of the dipstick cannot give a normal indication of the color quality of the fluid inside the gearbox. To understand this, it is necessary, using a syringe and a dropper, to extract 30-50 ml of lubricant through the filler neck.

Normal oil color for automatic box gear - bright red cherry. The darker the color of the recovered solution, the more urgent the need to replace it. A dark color indicates contamination of the lubricant with wear products and oxidation. This leads to increased fuel consumption, jerky gear changes, wear and gearbox failure.

But the touch in the oil should not be felt by excess elements and particles. If there are any, then particles are generated from rubbing and touching parts. This can lead to their early decommissioning.

In addition, the oil solution can be sniffed. A bitter and burning odor can be an indicator that it has lost its performance. Any deviation of the tested grease from the original state may become a reason for its immediate replacement. Timely replacement fluids and compliance with the manufacturer's recommendations significantly affect the service life of an automatic transmission.

Conclusion

Determination of the lubricant level in an automatic transmission is not only mandatory within the time specified by the manufacturer. It can be carried out independently if the lubricant deviates from the norm or if the gearbox malfunctions. If you have no desire or opportunity to do such work yourself, use the services of specialized companies.

Many well-known automakers assure that the oil in the automatic transmission does not need to be replaced during the entire operational period. Regular vehicle maintenance and timely level control in automatic transmissions reduces the risk of serious damage. Drivers with experience in car care can easily check the automatic transmission oil level in garage conditionswithout waiting for deterioration in work. The instruction manual for a particular model contains detailed information on the procedure for carrying out control and measuring works.

Why check the oil level

In addition to reducing the friction force between the brake clutches, ATF lubricant performs the functions of removing excess heat, preventing the accumulation of deposits on metal surfaces, cleaning parts from carbon deposits, chips, etc. If the volume of oil in an automatic transmission decreases, the risks of the following negative processes significantly increase:

1. Destruction of metal surfaces of assemblies and parts.
2. Sticking when shifting gears.
3. An increase in temperature leads to a decrease in the mechanical strength of metal and polymer surfaces.
4. Incorrect operation of the box (does not respond to switching or works with a delay).

At the same time, the frequency of occurrence of problems and the intensity of their manifestation are steadily increasing.Even the slightest deviations in the operation of the transmission are not recommended to be ignored. If there are alarming symptoms, the first step is to check the oil in the automatic transmission. If no leaks are found, but the oil has changed in color and consistency, it is recommended to urgently contact the nearest service station. Delay in both diagnostics and repair can lead to irreversible changes in the gearbox.

The oil level in the automatic transmission is not only reduced, it must also not exceed a predetermined limit. Incorrect oil filling can lead to unintended consequences:

• upon reaching the edges of the rotating parts, the solution begins to foam, the workers
• the characteristics of the oil are rapidly decreasing, the production of lubricant is sharply accelerated;
• problems similar to a lack of oil appear;
• excess oily substance flows out through the breather;
• the case of the automatic box is covered with oil drips from the outside.

How to check the oil level in an automatic transmission with a dipstick

By measuring the oil level, the owner of the car can detect a leak in time, as well as the degree of wear of the lubricant in the automatic transmission. The information obtained is necessary for the right choice car repair methods. The design of the new automatic transmission is significantly different from the usual mechanical devices. Many drivers have certain difficulties when trying to determine the oil level in an automatic transmission for the first time.

As a rule, the dipstick for measuring the oil level in the automatic transmission is easy to see on the box body. Automakers have tried to visually distinguish the oil dipstick against the surrounding body parts. Its handle is marked with a contrasting color (yellow, red, etc.).

The procedure for measuring the oil level in an automatic transmission with a dipstick

1. Place the vehicle on a level surface with no slope.
2. Move the gear lever () to the “Parking” point.
3. Warm up the engine to plus 90 ° С.

The dipstick has special MAX and MIN control notches. They are located in pairs on opposite surfaces of this instrument and are designed to measure the oil level in different temperature conditions (COLD-cold, HOT-hot). The "cold" test is carried out at an ambient temperature above 0 ° C.

The oil level in the automatic transmission is considered normal if the oil trail is between the minimum and maximum marks.

We measure the oil level in the automatic transmission without a dipstick

There are cars (as a rule, these are European models), the design of which includes only one control probe - for measuring gasoline in fuel tank... Here, the transmission oil level in the automatic transmission is checked without using a special oil dipstick.

In this case, the design of modern automatic transmissions provides for the installation of a special tube in the sump of the box. The protective tube is designed to drain excess and control the condition of ATF transmission oil by the smell of burning, dark color, consistency density, and changed chemical composition.

Verification steps:

• after a thorough analysis of the quality of the oil inside the automatic transmission, the tube is screwed into place;
• a portion of fresh oil is added through the filler hole using a special flexible hose of a suitable diameter and a funnel;
• if nothing flows out through the control tube, you need to add lubricant until oil drops appear (the box begins to get rid of unnecessary excess).

Checking the oil level in the automatic transmission yourself is not a difficult procedure. However, before holding this event, you need to familiarize yourself with some of the nuances. If you do not take them into account, large errors are obtained when measuring the oil level.

Experienced motorists know that there are multiple cavities inside the automatic gearbox in the oil compartment in which large quantities of gear oil are collected. As a consequence, the probe readings are not always reliable. Measurements are considered correct if the oil level is measured not once, but in several passes (after one or two days). The arithmetic mean of the readings is then calculated.

The dipstick for measuring the level of ATF transmission oil is very similar in appearance to the control device designed to check the oil c. Before use, you must carefully examine this device so as not to confuse it with a "motor brother".

In cars with rear wheel drive the automatic transmission oil dipstick can be difficult to find, since it is located between the interior wall and the engine compartment. After a thorough examination of this space, it will definitely be found.

Regardless of the design of the machine, it is necessary to measure the oil level only after thoroughly warming up the box.

Automatic gearbox is a design that for several decades could be found only on expensive cars foreign production. Today, automatic transmission is far from an exclusive phenomenon; many cars, both domestic and foreign, are equipped with such a system that greatly simplifies the life of the car owner in terms of driving. When operating a machine, you can forget about the clutch pedal, which must be depressed regularly when changing gears in mechanical systems.

Regulations for the correct check of the oil level in the automatic transmission.

An automated gearshift system is a complex mechanism that requires constant proper care, since its failure can threaten significant financial costs. And the main focus of caring for the automatic transmission is the regular monitoring of the oil in the system, its replacement as soon as necessary. In this article, we will figure out how to check the level, what its volume is considered to be the norm, and what is the threat of a decreased or increased amount.

How to check the oil level in the automatic transmission?

The presence and compliance with the norm of the lubricating fluid guarantees controllability and reliability in the operation of the vehicle due to the correct functioning of the transmission units. Failures in the automatic transmission is exactly the case that is better to prevent than to eliminate the consequences later. Automatic system is quite expensive, and its repair also does not belong to the category of penny costs.

An effective measure to prevent automatic transmission malfunctions is considered to be a periodic check of the indicators and condition of the oil, as well as replacement if the lubricant has already worked out. The procedure for monitoring the criteria of the lubricating fluid is not particularly complicated and does not take much time, therefore, any person, having familiarized himself with the methodology of its implementation, will be able, by spending a few minutes at intervals of several weeks, to prevent serious machine breakdowns.

It is best to look for the correct answer to the question of how to check the oil level in an automatic transmission correctly in the user manual for the vehicle, where the manufacturer describes this procedure step by step. If for some reason you cannot use the instructions, then we will tell you in detail how to check the oil level in an automatic transmission of various modifications.

Probe modified box

The overwhelming majority of modern vehicles are equipped with an automatic transmission with a special dipstick, which is provided by the car manufacturer for routine check of the oil in the transmission by the owner of the car. The first task for the car owner is to find out where the automatic transmission oil level dipstick is located, and whether it is in this car model. You can find out where the dipstick is located in the user manual or by self-study. engine compartment... Most often, the device is located near the back of the motor, closer to the partition engine compartment... In order to see it, you need to open the hood and stand in front of the car, across its movement. The desired part is located on the right hand, looks like a handle painted in a colorful color, on the left hand there is also a dipstick - this is a device for monitoring the oil in the power unit.

In some models of cars, there are two dipsticks next to it: to check the lubricant level in the engine and in the gearbox, then you will have to navigate by the color of the handle of the device. As a rule, the lubrication dipstick in the motor has yellow, and the other handle will be painted in a different bright shade - this is the dipstick for monitoring the oil level in the automatic transmission.

Once the tools are found, you can begin to test the criteria for the lubricating fluid. If the car owner pulls out the dipstick for a visual inspection, he will see that the device has two engravings - COLD and HOT - with two marks next to each of the values. The specific marking of the stylus is very different from its standard type in mechanical boxes... The fact is that this procedure can be performed in two ways: the first is control on a cold automatic transmission, which gives an estimated result, the second is an accurate monitoring of the fluid level on a heated box to operating degrees. Let's consider what the oil level in the automatic transmission should be on the dipstick when checking it in different ways.

For diagnosis, regardless of the method, it is important to place the car on an extremely flat horizontal surface.

Level control on a cold automatic transmission is carried out in the following way:

The results of checking the oil criteria for a hot automatic transmission are considered more reliable. Before performing the procedure, you need to warm up the car to operating temperatures, having driven it for about fifteen kilometers. Run the box in all positions, with the motor running, check the level according to point 2 above the instructions provided.

Estimate the oil level against the HOT reading on the dipstick. The norm is the position of the oil level between the marks near the inscription HOT. With an increased or decreased level of lubricant, it is required to extract it or topping up to the level, respectively. This method of verification gives more reliable and error-free data if the procedure is performed correctly. Professionals advise checking the level only after the transmission oil has warmed up to operating temperatures in order to obtain the most accurate results.

Box without probe

The methodology for diagnosing the lubricant level using a dipstick is not particularly complicated and can be performed by any car owner independently. How to check the oil level if the vehicle is not equipped with a dipstick from the factory? In vehicles equipped with automatic transmissions without a dipstick, it is most often not supposed to replace the emulsion throughout the entire operational period of the machine, or the automaker is trying in this way to combat unauthorized interventions in the transmission system, providing for its maintenance exclusively.

Automatic boxes without a dipstick have only two holes - oil drain and oil filling opening. In these boxes, excess lubrication is not possible, since the system is equipped with a special tube through which excess fluid is removed into the sump during the operation of the machine. However, it is much more difficult to determine the decrease in oil indicators in such automatic transmission modifications, to find out its level is much more difficult than in the previous case, because if you are not one hundred percent confident in your abilities, then it is better to abandon this venture, use the services of professionals.

Let's consider step by step how current craftsmen check the oil level in an automatic transmission at home:

When checking the lubricant level in parallel, it is important to evaluate its appearance for impurities and slag components, which are an indicator for. Having figured out how to check the oil level in the automatic transmission and having carried out this procedure on his own at least once, the car owner will forever save himself from the need to regularly visit the service station for this purpose, significantly saving his budget. Let's figure out further than underfilling and fluid overflows are dangerous for the gearbox, what will happen if the problem is not detected in time, or simply ignored such precedents.

The consequences of operating the machine with a reduced liquid level in the automatic transmission

For new car owners, the only way to detect a low oil level is to check its criteria using the above regulations. but experienced drivers automatic transmissions can determine a low oil level even by the behavior and reaction of the car on the road, based on the following symptoms:

• deterioration in vehicle handling;
• appearance from the side of transmission units;
• reduced response of the car to gear shifting.

These circumstances inform the driver that the automatic transmission has a low oil level; accordingly, it needs to be refilled to normal or the lubricant must be replaced if the car has been operated for a long period in the mode of oil starvation of transmission units.

Why are situations when the level of emulsion in the box is below normal are so dangerous? The fact is that fluid circulation in the system is ensured by pumping it with an oil pump. If there is a shortage of fluid in the system, the pump begins to capture air along with the lubricant, driving it through the system. The consequence of such a precedent is the compression of oil under air pressure, which results in poor-quality lubrication of the contacting parts and the emergence of a huge number of metal chips in the liquid, which special magnetic elements do not have time to sift out. The contaminated oil, circulating through the system, does not cope with its tasks, which leads to deformation and wear of working working units.

Increased oil level in automatic transmission: how dangerous is it?

The situation with an excess of oil in the automatic transmission is possible only in cars that have been modified with a dipstick. In boxes not equipped with a dipstick, excess oil is automatically dumped through a special tube, which excludes the possibility of such precedents. An elevated lubricant level is considered, which, when checked, is noted above the maximum mark on the dipstick. An abundance of lubricant in an automatic transmission is no less dangerous for the box than its deficiency. With an excess of fluid, its strong foaming occurs, the oil against the background of high operating temperatures begins to rapidly oxidize and evaporate, which is fraught with failure of valves and friction parts of the system.

When the machine is operated in the mode, the consequence will be a change in the composition of the oil at the molecular level, a decrease in its quality characteristics, which will affect the efficiency of its work and result in expensive repairs for the car owner. To avoid such consequences, it is important to regularly check the lubricant level according to the regulations; when replacing it at home, strictly follow the automaker's recommendations for the optimal fluid displacement.

The optimum oil level in the machine is its criteria on the dipstick approximately halfway between the minimum and maximum marks, and the markings on the dipstick are the extreme permissible liquid limits. Experienced car owners and professionals advise diagnosing oil readings in automatic transmissions according to the following recommendations:

• carry out checks according to the manufacturer's regulations;
• do not ignore even the smallest deviations from the lubricant fluid;
• when checking the level, assess not only the filling of the system, but also visually analyze the state of the liquid for impurities and coarse particles, and make scheduled oil changes in accordance with the regulations.

Let's sum up

Controlling the oil indicators in the automatic transmission is the direct responsibility of each car owner, since the reliability, controllability and safety of the car on the road depend on the quality of the automatic transmission. You can accomplish the task both on your own and using the services of service center workers, which will be cheaper than repairing the box or replacing it.

This article provides instructions for performing these operations on different modifications. automatic gearboxesinstalled on cars, according to which even an inexperienced car owner can learn to control the lubrication level in the automatic transmission of his car on his own. This will help you not to miss the moment when the oil criteria deviate from the level, to take preventive steps to troubleshoot in time.

Modern cars are becoming more and more perfect every year, but this perfection also entails the need for proper maintenance and control over the performance of components and assemblies. For example, the same rather complicated technical mechanismrequiring appropriate service and control over it technical condition, we read. By the way, it will probably not be superfluous to recall how you need to monitor the automatic gearbox.

The most important thing in automatic transmission diagnostics is constant monitoring of the oil level in it, its color and smell. Yes, it is the oil that will give you a signal about possible imminent troubles that may occur with this unit of the car.

How to check the oil level in an automatic transmission - instructions.

Therefore, the first step is to regularly check the oil level. Many cars assume different steps for performing this procedure, but most of them boil down to the following steps.

By the way, if you changed it yourself, here is an article, or at least purchased oil, do not be too lazy to smell it and look at its color. In the future, this information will be very useful to you during checks.

If the oil level is normal, the color corresponds to the color of the filled oil, and there are no extraneous odors, then with general sensations of normal operation of the automatic transmission, the check showed about normal work your unit.

If the oil level is below the specified mark, then, firstly, you should think about adding it to the required rate. A low oil level is fraught with overheating of the machine, a decrease in its resource, as well as a decrease in pressure in the system and, as a result, failure of this unit of your car. Secondly, it is worth thinking about the reason for the drop in the oil level, and, perhaps, contacting a service for diagnostics.

If the oil level is above the mark, you can expect, due to excess pressure, the release of oil from the automatic transmission housing, as well as all the troubles that occur with a low oil level, concerning the violation of the thermal regime. As a consequence of all this, the wear of the box is accelerated.

By the way, foaming will also be a characteristic sign of an improper oil level due to the above reasons, which you will definitely notice on the dipstick.

Topping up oil, if necessary, is done gradually on a cold engine, as you already understood, according to the "COLD" label.

And finally, I want to note once again that the procedure described above is relevant for most cars, but on some of them it may differ. For example, there will be only one mark or the check will be performed in other automatic transmission modes. Therefore, in any case, I strongly recommend reading the operating instructions for your car. By the way, you can read about the advantages of an automatic transmission in the article