Most vehicle owners know that they need to stay abreast of routine maintenance such as oil and tire rotation in order to keep their journey ready to drive. You should also keep an eye on your automatic transmission though, which you know, the thing about the gears you shift into drive, reverse, and park several times a day. A smooth hum from your transmission can pay off because it’s one of the most expensive components of your car to repair or replace.
Fortunately, checking the health of your transmission is not as difficult, time-consuming, or costly as you might think. Here is how.
Checking the Transmission Fluid
Just as your engine uses oil to lubricate and cool its internal parts, automatic transmissions use specially formulated transmission fluid for the same purpose. Conventional automatic transmissions, dual-clutch automatic transmissions, and continuously variable transmissions each use a certain type of transmission oil.
If you are not sure which fluid is used in your transmission, read the owner’s manual. You can usually find the requirements for the transmission fluid in the section with the technical data.
You don’t have to be a mechanic to get an inside look at the condition of your vehicle’s transmission. A simple visual inspection is sufficient. You need to check the level and condition of your transmission fluid.
When to check transmission fluid hot or cold?
Turn on your car, leaving it in park, and let the engine run for a few minutes to warm up. Transmission fluid expands in heat and in order to receive accurate results, it must be under normal operating conditions. If the fluid is checked when the engine is cold, you may get false results indicating the fluid is low.
The decision on whether to check transmission fluid hot or cold depends on the type of vehicle you are using. Most mechanics recommend checking the transmission fluid when both hot and cold. This helps you to cross-check on the levels of the fluid when both hot or cold. The reason why you should check when hot or cold is that the fluid expands when heated.
When you have been running your vehicle for a long time and then check the fluid level when hot, it may appear to be high, while in the real sense, it is low. If you have to check it when hot, then you do not do that after driving for a long period. This is because the fluid continues to expand the hotter it gets.
Therefore, you check it when it is normal hot as if you have been traveling for around 10 miles or a little longer during the winter season.
Locate the Dipstick
First, locate the transmission’s dipstick, located under the bonnet, in the engine compartment. Be sure to locate the transmission dipstick and not the engine oil dipstick. The transmission dipstick is usually located further back in the engine compartment, facing the firewall (bulkhead on the front of the cab). The transmission dipstick is usually marked with a specific color or a transmission symbol.
Note: If you cannot find the dipstick, don’t be alarmed. Many modern vehicles use a life sealed transmission that never needs to be checked or replaced, so they don’t have a dipstick. (For information about the specific maintenance schedule for your model and how to check that it has a dipstick for the transmission, see the owner’s manual.)
If your vehicle has a sealed transmission, you can slam the hood and drive. However, if your vehicle has an oil dipstick, here’s what to do next:
How to check transmission fluid level?
With the engine warmed up, leave the car idling in park on a level surface. Pull out the dipstick, wipe it clean, replace it slowly, and then pull it back out. Check the fluid level, how high the fluid comes up on the dipstick, against the “full” and “low” or “fill” marks on the dipstick.
To check your automatic transmission fluid, follow these steps:
- Pull out the dipstick. With the gearshift in Neutral or Park and the parking brake on, let your engine run. Be sure the engine is warm when you pull out the dipstick. (Don’t turn off the engine.)
- Check the fluid. Dip the tip of your index finger into the fluid on the dipstick and rub the fluid between your finger and the tip of your thumb. The transmission fluid on the dipstick should be pinkish and almost clear. If it looks or smells burnt or has particles in it, have a mechanic drain and change the fluid.
- Wipe the dipstick with a clean, lint-free rag; then reinsert it and pull it out again. If the transmission fluid is clear but doesn’t reach the “Full” line on the dipstick, use a funnel to pour just enough transmission fluid down the dipstick tube to reach the line. Don’t overfill!
The color of transmission fluid can tell you a lot about the health of your car’s transmission.
Now place the dipstick on a white surface, such as a paper towel to analyze the color of the liquid. The condition of your transmission fluid, and to some extent the transmission itself, is indicated by the color of the fluid. If your fluid is healthy, it should be reddish-pink in color. When the time comes to replace it, it’s brownish red. If the liquid is dark brown or black, it is entirely possible that you are replacing more than just your liquid.
Dark liquid with a burnt odor is bad news. In the worst-case scenario, you may also find fine metal filings in the liquid. Both symptoms indicate possible damage to the internal components of your transmission.
This is usually due to the fact that the recommended maintenance interval for replacing the transmission fluid is not observed. However, it is not impossible for transmission, like any other component of the vehicle, to experience a premature mechanical problem.
If your fluids are low, it doesn’t necessarily mean you are headed for disaster, but it most likely means that there is a leak somewhere in the system. Refilling the transmission and checking it daily to see how quickly the level is dropping can be a great way to assess the severity of a potential leak.
Also, try to visually check your transmission by looking for leaks under the car. Does the car leave reddish fluid stains on the floor after parking? If the fluid is black, it’s engine oil. If it’s water, it’s likely condensation from the air conditioner.
If you experience loss of transmission fluid, or if you find that your transmission is using an abnormal amount of fluid, contact a mechanic as soon as possible. We recommend that you go to a reputable car dealer who will sell and service your vehicle as the first stop.
The service department has the most experience with your make and model and may have seen this problem before. If you have the luxury of leaving the car until it can be inspected, do so.
Contrary to the statements of some internet mechanics, exchanging the transmission fluid does not destroy the aging transmission of an older vehicle. If a transmission suddenly has problems after replacing the fluid, it is usually because an internal problem has already occurred, such as a problem with the transmission. such as a worn clutch pack. If your transmission is healthy, a fresh fluid change will only help longevity.
FYI, if your transmission fluid is low and needs topping up, it is usually through the same tube that the dipstick fits. Adding liquid (which is available at auto parts stores) requires a funnel with a narrow and most likely long funnel spout.
Like any machine, a transmission must be properly maintained in order for it to function as intended by the manufacturer. As they say, take care of your transmission, and it will take care of you.