Check transmission oil: A step-by-step guide

Not only your vehicle engine, but also the gearbox needs sufficient lubricant for the right function. This minimizes wear and tear and optimizes efficiency. You must also regularly check your transmission oil and its level to keep your vehicle in good condition. In this way, you can easily see whether it is necessary to change your transmission oil early.

How can you check the transmission oil level in your automatic transmission?

Automatic transmissions often require certain maintenance related to the existing lubricant. If your own vehicle model is equipped with an automatic transmission, a suitable transmission oil dipstick is usually also available. In many cases, this is red in color, while the engine oil dipstick is often marked in white or yellow. In addition, there is usually also a suitable label. On models that are front-wheel drive you will most likely find the rod on your driver's side transmission, on rear-wheel drive models it is often near the rear of your vehicle's engine on the passenger side. If you cannot immediately find the right dipstick in your engine compartment, we recommend taking a look at your vehicle operating instructions. There you will also find information about which gear oil is used in your vehicle.

To check the exact level of the gear oil, you must first pull the dipstick out completely. You should then use a lint-free cloth to wipe all of the gear oil off the dipstick. Then reinsert the dipstick and wait a few seconds before it can be pulled out again and read. There are markings on the oil dipstick for the maximum and minimum oil level. If this is below the minimum, you must top up with the appropriate gear oil. It is advisable to pay attention to the quantity. If you have to add more than 25% of the required volume or if the gear oil level is often too low during a check, further diagnostic steps are necessary. In such a case, it is important to understand where your gear oil is going.

Another important piece of information is the color of your gear oil. So-called ATF gear oil for your automatic transmission impresses with its bright red color. You should also pay attention to any particles and/or burning smells that may be present. Both symptoms indicate that a thorough transmission diagnosis should be carried out.

How do I check the transmission oil level on a manual transmission?

This is usually not necessary and often not intended. Only very few manual transmissions have a suitable transmission oil dipstick. If you need further information or want to know if and when you need to change your transmission oil, we recommend that you take a look at your technical operating instructions. However, there are also situations in which it is advisable to replace your gear lubricant. This includes in particular all vehicle repairs that affect your transmission.

How do you top up transmission oil?

Before starting this work, you should check your gear oil level. It is usually sufficient to use the associated dipstick, as described above. In general, you should only use the right gear oil for all refill work. Your vehicle manufacturer usually provides detailed information on the lubricant used. Such information can be found in your vehicle manual. If you want to change your transmission oil, we recommend that you also replace the transmission oil filter at the same time. This ensures that any particles are filtered out.

Common types of oil for automatic transmissions are the 75W90, 80W90 and 75W140 transmission oils. In the first step, you should definitely find out which transmission oils are approved and which ones are currently in your vehicle. This is the only way you will be able to identify the right product so that your vehicle transmission will continue to work faultlessly for a long time. Since the filling opening on most transmission oil expansion tanks is rather small, we recommend that you use a suitable funnel if you want to top up. On the other hand, if you want to completely change the transmission oil, you can expect in most cases that at least 3-4 liters of transmission oil will be required for your vehicle.

So that you can distribute your gear oil optimally, you should gradually engage all gears after filling. Of course, it is best if the vehicle wheels can rotate freely in the air, because this distribution should take place without additional load(s) if possible. It's a good idea to leave your engine running and „drive“ your vehicle in each gear for at least a minute. to let. After you have shifted through all gears and driven it, it is still a good idea to wait a few minutes before switching off the vehicle's engine. This is the only way for it to reach all associated gears so that all transmission components are optimally lubricated. Now check the gear oil level again to make sure you don't overflow your gear lube. A possible lack of transmission oil can now be recognized quickly so that you can take appropriate countermeasures.

Conclusion

Checking the gear oil is a task that even less experienced mechanics can do on their own. A suitable oil dipstick, which works in the same way as the oil dipstick of your engine oil, usually helps. In this way, you not only receive information about the oil level, but also about the color of your transmission oil. The latter gives you an indication of how heavily the transmission oil has already been used.

A tip from CarTipsandmore:

  1. If you drive a vehicle with a manual transmission, you must usually not worry about the gear oil. This type of gearbox is usually sufficiently filled at the factory and, depending on repair work, no replacement is necessary. An automatic transmission, on the other hand, often has a matching oil dipstick. You can also find more information in the technical operating instructions for your vehicle.
  2. If you top up transmission oil, you should do this very slowly and in small doses. This makes it easy to fill up with a little more oil if it is too little. On the other hand, it is very difficult to get rid of excess gear oil.