How to add transmission fluid

Changing your vehicle’s automatic transmission fluid (ATF) isn’t as simple as changing its oil, but you can still do it yourself. Be sure to check your vehicle’s service manual beforehand, in case your model requires special procedures or needs extra care. Changing the transmission fluid is considered part of regular car maintenance.

Be sure you buy the right transmission fluid and parts even if you have to cough up extra money. Getting the wrong fluid or parts may damage your transmission.

Tools Needed

You’ll need a few extra items besides your standard toolbox contents.

  • A transmission filter and gasket plus gasket adhesive.
  • Transmission fluid.
  • A large catch pan.
  • Socket wrenches, screwdrivers and a mallet.
  • Clean cloths and safety glasses.

Cat litter comes in handy to soak up any fluid you spill. To clean the fluid pan, parts cleaner or a similar solvent is useful.

Partial or Full Change?

There are ways to drain and replace all the fluid in your transmission, but the simplest way for beginners is to do a partial replacement. If your vehicle is long overdue for a fluid change and you’re new at doing it yourself, you should probably take it to your neighborhood auto mechanic. As you get more experienced at changing ATF, you can teach yourself to pump all the fluid out through the dipstick filler or one of the cooler lines.

Before you begin changing the fluid, examine it with the dipstick. If it looks good (red) and smells normal (like petroleum), you’re okay changing it yourself. If it smells or looks burnt, this could indicate transmission problems, requiring the trained eye of a mechanic. Most manufacturers recommend an automatic transmission fluid change every 25,000 to 30,000 miles.

The method in this article drains almost half of the automatic transmission fluid and replaces it with fresh fluid.

Instructions for Changing Automatic Transmission Fluid

First, locate your vehicle’s transmission pan. In some vehicles, you might have to remove sections of the exhaust system. Place a large catch pan under the transmission pan and begin loosening the bolts. Do not remove them all at once, as this will cause a mess. Instead, remove the bolts from all but one side, and then tap the pan to help break the seal. Then slowly remove the remaining bolts in order to slowly tilt the pan away from you and drain into the catch pan.

Measure the old fluid so you know how much to replace. You can do this by pouring it into empty one-gallon milk jugs. Once the bulk of the fluid has drained, remove the other bolts and the pan so you can change the transmission filter. Be careful to keep the pan level, as there will still be plenty of fluid left.

Next, remove the used gasket. Clean any debris from the transmission and transmission pan and its sealing surfaces with parts cleaner or a solvent such as brake cleaner, or a gasket scraper. Make sure to replace the magnet back inside the pan after cleaning, if present, as it is prone to attract metallic parts that would otherwise end up in the transmission and inflict damage.

Remove the old transmission filter. If it is not bolted, the filter will simply pull off with a twisting and pulling motion. If it is of the “pull off” variety, there is usually a new seal that accompanies the filter kit. Be very careful when removing the old seal. If you are worried about damaging or scratching the seal bore, just reuse the old seal.

Finishing Up

Next, install the new filter. Push it into place by hand, or fasten with the attaching screws. If the transmission’s original gasket was ridged rubber, and the new one is cork, you should reuse the original gasket, provided it is undamaged as it is considered a reusable gasket and has superior sealing capabilities to cork. If you are replacing a cork gasket with a new cork gasket, then lay the new gasket onto the clean pan making sure that all of the bolt holes line properly and that the gasket is not upside down. Poke the bolts through the bottom of the pan and up through the gasket. The new gasket will hold the bolts in place. Attach the transmission pan to the transmission. If you do not have a torque specification for the pan bolts, just make the bolts “screwdriver tight.”

Finally, add the new transmission fluid. Most vehicles allow you to do this through a dipstick tube. Some vehicles require the fluid to be injected through a plugged hole in the transmission while running in park. Start by adding the amount of fluid that has been drained. Then take your vehicle for a short drive and shift through all of the gears.

Last, double check the fluid level. Most vehicles say to check while “hot”. This refers to when the dipstick is hot to the touch. Do not overfill the system. You can repeat the flush one or two more times to get all of the fluid replaced with new liquid, but this isn’t necessary. As long as you maintain your vehicle’s transmission fluid, a partial change every 25,000 to 30,000 miles will suffice.

Remember to seal the used fluid in a container and take it in for recycling. Check with your local recycling center to find out how to properly dispose. Many garages in colder climates will take this from you to fuel waste oil heaters.

The basic definition of a transmission is the part of a vehicle that transfers the power from the engine to the wheels. How a transmission works depends on whether or not the vehicle is an automatic or a manual.

Manual vs. automatic transmissions

A manual transmission has a set of gears that are lined up on a shaft. As the gearshift and clutch, located inside the car, are manipulated by the driver, the gears move into place. As the clutch is released, power from the engine is transmitted to the wheels. The amount of power, or torque, is dependent upon the gear that was chosen.

With an automatic transmission, the gears are lined up on the shaft, but the gears change by manipulation of the gas pedal inside the car. As the driver presses on the gas pedal, the gears shift up automatically depending on the current speed. If the pressure on the gas pedal is released, the gears cycle down, again depending on the current speed.

Transmission fluid lubricates the gears and makes it easier for them to move as the process of switching gears is completed.

How often do I need to replace the transmission fluid?

Again, this depends on if the vehicle is automatic or manual. In an automatic transmission, there is higher heat produced, which means that there’s going to be more carbon produced, which will contaminate the transmission fluid. Over time, these contaminants will cause the fluid to thicken and no longer do its job effectively. Manufacturer specifications for automatic transmission fluid vary considerably, from 30,000 miles to never. Even if the user’s manual says that the fluid will last the lifetime of the car, the fluid level should be checked periodically, in case a leak develops.

In a manual transmission, the recommendations can also vary widely, but for different reasons. Most manufacturers suggest 30,000 to 60,000 miles as the point at which you should change the transmission fluid in a manual transmission. However, vehicles with transmissions that are under ‘high stress’ should change the transmission fluid every 15,000 miles. ‘High stress’ for a manual transmission would be situations such as being driven on lots of short trips where gears are changed more often. If you live in a city and rarely put any highway miles on your vehicle, the transmission is under high stress. Other situations include lots of mountain driving, and any period when a new driver is learning how to use a manual transmission.

Signs you should check your transmission

Even if you haven’t reached the mileage threshold indicated by the vehicle’s user’s manual, the transmission should be checked if the following symptoms are noticed:

If a grinding sound is heard from underneath the vehicle while the engine is running, but the car is not moving.

If you have problems shifting gears.

If the vehicle slips out of gear, or if the vehicle doesn’t move when the gas pedal is pushed.

Occasionally, the transmission fluid can become contaminated to such a level that it needs to be flushed before the manufacturer specifies.

No matter the type of transmission, changing the transmission fluid is not a quick process that can be taken care of with a wrench and a nozzle. The vehicle will need to be supported, and the old fluid will need to be drained, and disposed of properly. Furthermore, the transmission fluid filter and gaskets will need to be inspected. This is the type of vehicle maintenance that needs to be left to licensed mechanics rather than attempted at home.

Next Step

Schedule Transmission Fluid Service

The most popular service booked by readers of this article is Transmission Fluid Service. YourMechanic’s technicians bring the dealership to you by performing this job at your home or office 7-days a week between 7AM-9PM. We currently cover over 2,000 cities and have 100k+ 5-star reviews. LEARN MORE

Unless you drive an electric vehicle, your vehicle has some type of transmission fluid. Usually, when people mention “transmission fluid,” they’re referring to automatic transmissions, but it does one good to note that all transmissions use transmission fluid of one type or another. What that transmission fluid or gear oil does depends on the type of transmission, and we’ll get to that in a moment.

Like all engine fluids, transmission fluids have a limited lifespan, which means they must be periodically replaced. Some transmissions include a filter, to remove metal flakes and carbon, as well as magnets, to catch steel particles from internal wear. Depending on the vehicle, transmission fluid replacement may be recommended every 30,000, 60,000, or 100,000 miles – some have no recommended interval. If there is a transmission leak, caused by worn seals or an impact, then adding transmission fluid will keep the transmission running until the leak can be repaired.

Types of Transmission Fluid

There are generally two types of transmission fluid, formulated for either manual or automatic transmissions, and they are not interchangeable. The reason for this is because manual and automatic transmissions use transmission fluid in different ways. Manual transmissions use transmission fluid mainly for lubrication and heat moderation, while automatic transmissions use transmission fluid for these, and as hydraulic fluid, for pressure-operated valves, clutches, and brakes.

Within each group of transmission fluids, manual or automatic, there are several types and additives, depending on transmission type, gear type, and automaker. The most basic manual transmission fluid is simply a heavy gear oil, something like 75W-90 or GL-5, but some manual transmissions require additive friction modifiers for the smooth operation of gear synchronizers. Differentials use similar gear oil, but likely different additives for limited-slip clutches and the like. Automatic transmission fluid types vary widely, such as Mercon V, T-IV, and Dexron 4, depending on YMM (year, make, model) of the vehicle in question.

Whatever vehicle in question, it is critical to only use the appropriate transmission fluid for that application. In a pinch, substituting 100-weight gear oil won’t hurt a manual transmission requiring 75W-90, though you might experience slower shifting and decreased fuel economy. On the other hand, adding Mercon V to an automatic transmission requiring T-IV could be disastrous – it might run for a while, but it would eventually destroy any incompatible seals or clutch materials, costing thousands in transmission rebuilding costs. Always refer to a YMM-specific repair manual or owner’s manual for transmission fluid specifications.

1. Make sure the fluid is warm. Warm up the car so the transmission is at normal operating temperature. Pull the transmission dipstick (located near the firewall in most cars). Fresh fluid is translucent and cherry red. Some darkening is normal, but if it is reddish brown or mustard color and smells like burnt varnish, it is worn out.

2. Drain the fluid by loosening the pan. Select the correct transmission filter replacement based on pan shape and prepare a large pan to catch the fluid. Then loosen each pan bolt a turn or two and loosen one corner more than rest. Drain mostly from this corner. See our application guide to find the correct filter for your vehicle.

3. Finish removing the pan and any gasket material from the pan or case. Avoid scratching the metal and make sure the pan’s gasket surface isn’t bent or distorted.

4. Remove the old filter. Most transmission filters are held in place with a bolt or two, but some are held by a clip. Be careful to include O-Rings or other seals.

5. Install a new filter. Use the clips or bolts from the old filter. Be sure O-Rings, etc. are in place. If the filter has a long intake neck, gently push the neck into place without unseating the O-Ring.

6. Clean the pan thoroughly. Inspect the pan before cleaning. A small amount of fine grey clutch dust is normal. However, if you find metal shavings, there has been transmission damage. Clean the pan with solvent and wipe dry so there is no harmful residue.

7. Position gasket on pan. Some gaskets have four holes slightly smaller than the rest to allow four bolts through the pan and through these smaller holes to hold the gasket in place.

8. Hand tighten pan bolts in a criss-cross pattern. After that, use a torque wrench to tighten bolts to proper ft-lbs as per manufacturer.

9. Refill the transmission using only the amount shown as “refill capacity” in the owners manual or “AMSOIL Product Selection Guide,” using the type of fluid specified for the vehicle.

10. If doing only a partial fluid replacement, skip to instruction 12 below. If doing a complete fluid replacement, follow the steps in instruction 11.

11. You now have replaced the fluid in the pan. To replace the fluid in the torque converter and oil cooler also, follow these steps.

Step 1. Obtain the total system capacity of the vehicle from the manufacturer or AMSOIL. Have this amount readily available.

Step 2. Disconnect the oil cooler line from the oil cooler. As you may not know which is the pressure side and which is the return side, have both directed so the stream of fluid will be directed toward a receptacle.

Step 3. With another person, be prepared to add ATF to the fill area as it is being pumped out of the oil cooler line.

Step 4. Start the engine, and as the old fluid is pumped out, add fresh fluid to the pan.

Step 5. When either the fluid color brightens or the total capacity has been replaced, shut the engine off and re-attach the oil cooler line. All fluids has now been changed.

12. Recheck the fluid level. With the car on level ground, set the parking brake and the transmission in “Park” or “Neutral.” Let the engine idle for a few minutes. Shift the transmission into different positions before returning the lever to “Park” or “Neutral.” Check the fluid level again and check for leaks.

Fresh Transmission Fluid is Critical To a Smooth Operating Vehicle

How to add transmission fluid

Adding transmission fluid can sound daunting, but it is actually quite simple. Save a trip to the auto shop and some money by following this easy guide on how to add transmission fluid. We will also outline how to check your fluid levels, which you should do regularly to catch any potential problems early on.

Transmission fluid is what keeps your car’s manual or automatic transmission running smoothly, allowing you to properly shift gears. What you will need to check or fill your transmission is a clean rag or paper towel, a long funnel, and your car’s specific transmission fluid. Every vehicle is different — check your owner’s manual to see what type of fluid your car needs.

How To Check And Add Transmission Fluid

You must check your fluid levels while the car is warmed up to operating temperature. Some cars even require that you check it while the car is on and running. Refer to your owner’s manual to see if the car should be on or not. Regardless, the engine should at least be warmed up.

Your car should also be parked on a level surface to ensure you get an accurate reading on your fluid level. Put the vehicle in park and make sure your emergency brake is set.

(Before you get started, it’s worth noting that a few vehicles, such as some Ford-F150s, don’t provide under hood easy access to check your transmission fluid. Instead, on these vehicles, you must check and fill the transmission fluid by opening a bolt on the transmission itself. This is beyond the scope of this article.)

How to add transmission fluid

1. Locate the hood release and open your hood. The hood release can usually be found by where your left knee rests while driving. If you cannot find it, refer to your owner’s manual.

2. Locate the transmission dipstick. The transmission dipstick will have either a yellow/orange handle or it will be marked with writing or an icon. Do not confuse the transmission dipstick with the oil dipstick; they look very similar. If you are not sure, again, refer back to your owner’s manual.

3. Pull the transmission dipstick out and wipe it clean. You will need to wipe the dipstick clean so that you can properly measure the fluid level, once you reinsert it.

4. Reinsert the dipstick back to its original location and remove it again. This will show you your fluid level.

5. Check the fluid level on the dipstick. The fluid should be between the hash marks on the dipstick. If it is below the lower hash mark, you will need to add more fluid.

How to add transmission fluid

How To Add More Transmission Fluid

Next, it is time to add more fluid. First, make sure you check your owner’s manual to make sure you have the correct fluid for your specific vehicle and transmission. This is extremely important!

1. Place the funnel in the transmission check tube. The funnel will take the place of the dipstick.

2. Add the fluid in very small increments. It is important to add only a little bit at a time. You need to be careful about how much you are adding because you actually do not need that much. Remember, you can always add more, but it will be extremely difficult to take fluid out if you overfill the transmission.

3. Recheck the level with the dipstick after each pour. This will allow you to see how much more you need, and keep you from overfilling. When you reach a level that reaches the top hashmark, or the full marker on the dipstick, remove the funnel and return the dipstick to its original spot.

How to add transmission fluid

One day it might happen that instead of starting smoothly like it usually does, your automatic car might just hesitate, especially while shifting gears. The first thought that could come to your mind would pertain to something being wrong with the transmission system of your car. However, before stepping on the panic button and calling the mechanic, what you could do is check the level of transmission fluid.

Unless your vehicle relies on electricity for running, it is likely to use some variant of transmission fluid, which needs to be replaced once in a blue moon. Automatic transmission has been known to operate smoothly for thousands of miles, which is why it is usually taken for granted by car owners. However, given its limited lifespan, it runs out one day and the resultant friction in the system hinders with the smooth functioning of the car.

The process of adding fluid to your automatic transmission car is comprised of two stages, which are outlined as follows.

How to add transmission fluid

Stage 1 – Checking the Level of Fluid in the Car

Before adding fluid, it is imperative to check the existing level of fluid in the car and to do so you need gloves and a towel/rag. Then follow these steps:

  • Park your car on a level surface and ensure that the gear is in ‘Park/Neutral’ mode, leaving the engine to idle since it needs to be running for you to check the fluid level.
  • Pop open the hood by operating a switch and keep it raised at a comfortable height.
  • Locate the pipe which contains the transmission fluid and find the dipstick with the help of a manual.
  • In most automatic transmission vehicles, the dipstick comes with a handle, which can be used to extract it from the pipe. A rule of thumb in this regard says that dipstick in a front-wheel drive is usually placed in the front portion of the engine and in a rear-wheel drive it is placed towards the back of the engine.
  • Since the dipstick is likely to be smeared with fluid, you must have a towel or a rag ready at hand to wipe it immediately after having pulled it out.
  • Markings on the dipstick either read Hot/Cold or Full/Add and ideally fluid in the automatic transmission car should be between these levels. If the level is lower than these markings, it is an indication that a refill is in order.

At this stage you must make it a point to check the color and condition of the fluid. It should ideally be clear and pink, but sometimes it does turn out to be burnt, milky or smelly. These are signs of contamination and repairs and should be referred to a professional mechanic. Likewise, there might be air bubbles also, which implies the presence of too much fluid or the wrong variant being used.

Step 2 – Adding Fluid in the Automatic Transmission Car

To add fluid in the automatic transmission car, you must equip yourself with a funnel and a can of fluid. Next, following are the steps that you need to follow:

  • Identify the type of transmission fluid that would be right for your vehicle. Variant of fluid to be added is determined by types of transmission, gear and make of the car and is critical owing to the fact that the wrong type could cause severe damage to the system.
  • Insert the funnel into the tube which is meant to house the dipstick and add the transmission fluid in small quantities.
  • Having added a certain amount, check the level of fluid before adding any more so as to conform to the levels recommended in the manual.
  • Run the car through each of the gears all the way from first to drive, overdrive and reverse and stop at ‘park’ once again. Let the engine idle for some time as this would serve to warm up the fluid and ensure its circulation throughout the system.
  • Once again insert the dipstick to check the current level of fluid and add more if required. This is also the stage that will enable you to determine if there is a leakage in the system because the level of fluid will have fallen drastically.

How to add transmission fluid

Final Thoughts

Hesitation of the vehicle while starting is a symptom that could either mean a faulty transmission or low level of fluid in the system. Therefore, it is advisable to first check the level of fluid in the automatic transmission car rather than assume that the system might have broken down and incur the cost of replacement.


    – dummies – Your Mechanic


A Honda Civic’s Broken Heater Core Ended My Five-Year Flipping Profit Streak

You’d think a car like this would be easier to make money on than, say, a Fiat 500. But that was not my experience.

How to add transmission fluid

Transmission fluid is like the lubricating oil of the transmission system of a vehicle. It is not actually called oil, but it is an oily substance which lubricates the transmission’s components. The type of vehicle you’re driving will determine which type of transmission fluid you use in the transmission. The other determining factor is whether your vehicle’s transmission is automatic or manual. The manufacturer’s guide of your vehicle should specify the type of transmission fluid you need to use. So, you won’t need to do any guessing there.

Most people may elect to have their transmission fluid changed or added by a professional auto mechanic. However, this will likely cost you hundreds of dollars in additional maintenance expenses. It is possible for a layperson to change their own transmission fluid without incurring all these costs. They just need to learn the steps of how to change the transmission fluid properly.

Steps to Adding Transmission Fluid

1) The first step is to check how much transmission fluid is in your transmission. You need to start your engine and keep it running to do this. This will ensure that you can accurately measure the fluid level. Just set the vehicle to park and the emergency handbrake in the upward position. Sometimes the gear may need to be in neutral, depending on what the owner’s manual tells you to do. The ground surface below should be flat and leveled as well.

2) Lift open the hood and secure the lifting bar to keep the hood open. Find the transmission fluid pipe and the transmission dipstick. If you have trouble finding these things, let the owner’s manual guide you. The dipstick goes inside of the pipe. When you take it out, see where the level of the fluid stopped. If it stopped between the “Full” and “Add” markings, then it is okay. But if it is lower than the “Add” marking, then it means you need to add transmission fluid.

3) Assuming you need to add fluid, you can move on to this step. The two things you’re going to need are the transmission fluid and a funnel. The fluid should come in a can if you purchase it directly from the auto shop. Again, be sure to choose the right type of fluid which is compatible with your vehicle’s transmission.

4) When you have these accessories, you can begin adding the fluid to the transmission. This can be done by placing the funnel into the transmission fluid pipe and then gently pouring the transmission fluid into it. Only put a little bit of fluid in there at a time because you don’t want to overfill it. Keep checking the fluid level with your dipstick in between your pouring intervals. Stop before the fluid level gets to the “Full” marking.

5) Take out the funnel. Start cycling through the different gears of the transmission while the engine continues to run. This means shifting to first gear, second gear, driving gear, neutral gear and then finally stopping at the parking gear. Continue to let the engine run idle so that the new fluid can warm up and circulate throughout the transmission.

6) Check the fluid level one more time with the dip stick. If the level is still normal, then you are done adding the transmission fluid. But if the fluid has decreased, then it means you have a leak somewhere in the transmission system. The best thing to do is identify where the leak is coming from and then fix the leak. After that, you can try adding the transmission fluid again following the same process that is outlined here.

How to add transmission fluid

The only way to check the transmission fluid level is to actually check the transmission fluid level. Most vehicles’ owners manual will tell you where it’s located, but some may not.

Usually, the transmission fluid level can be checked from outside the vehicle. But if you can’t see the dipstick, there will be a dipstick inside the transmission that you will have to check. It’s hidden somewhere, usually right by where you connect the fluid line to the transmission.

To check the level with a dipstick, follow these steps:

<1>. Open the hood of your vehicle; if you can’t see the dipstick, consult your owner’s manual.
<2>. Locate the dipstick. It’s usually about 2-3 inches long and made of plastic. It’s usually at the bottom of the transmission and in the middle.
<3>. Check the fluid level. The transmission will have a red fluid line that goes straight to the transmission. There should be a line indicating the fluid level. It’s usually located just near the dipstick and should be marked at intervals up and down.

How to Add Transmission Fluid

Automatic transmission fluid is like a car’s lifeblood. It’s actually more than just a transmission fluid; it’s an entire lubricating system that provides smooth and controlled shifts in automatic vehicles.

The transmission fluid cools the transmission system and regulates the transmission valves. It also lubricates the gears and bearings as they rotate smoothly through the transmission, as well as collect and return excess fluid back to the transmission pan.

Automatic transmissions use different kinds of fluids. Your car’s manual will tell you which one to use. The recommended automatic transmission fluid has a neutral color that ranges from pale yellow to amber.

Fluid level is everything in a transmission. The transmission fluid is responsible for transferring all power from the engine to the transmission and then between the gears. In vehicles with computer-controlled transmissions, the fluid level is measured, and if levels drop below a certain point, a warning sign appears.

Low transmission fluid causes smoother shifts. But when it’s empty, the transmission will shift harshly, possibly damage your car’s internal parts, and even grind the gears.

Signs of Low Transmission Fluid

Your car loses power, it becomes over-heated and needs to be cool down before proceeding, or it hesitates when clicking in a gear. These are just some of the symptoms of low transmission fluid. Before you attempt to add transmission fluid, it’s helpful to understand what transmission fluid does. It is a lubricant that keeps all of the moving parts, and in particular the gears, of your transmission working smoothly. There are many signs to look for that indicate a transmission fluid problem, some of which are gas related. ***** You can add transmission fluid yourself, but the replacement of the filter is typically a more involved job and is best left to professionals.


Transmission fluid is essentially a mixture of oil and water. It is the oil that acts as a lubricant and will help you to move your vehicle.

You will know that it is time to add transmission fluid to your vehicle when your transmission shifts poorly or problems occur. Before you add transmission fluid, you should check your fluid level and color. The fluid should be of the same color that you use to refill it. The color can range anywhere between golden to dark red. The level of the fluid should fall between the minimum level and maximum levels. You can do this by checking the dipstick sent in the owner’s manual.

You can add the transmission fluid by following the instructions on the dipstick or the owner’s manual. It is easier to add transmission fluid when you have a transmission drain. You will need a drain pan and a wrench to use it.

If the transmission fluid is highly contaminated by the coolant or has very low levels, you may be leaking. Your vehicle’s radiator and lines could contain a leak. This should be checked immediately.

Transmission fluid is not checked very often by most car owners, whether they drive an automatic or standard car, yet it’s one of the easiest things to check and could be critical in catching a problem early and saving you money.

Read through this article to see what transmission fluid is, how to top it up, and why you should make sure there is always enough of it.

What is transmission fluid?

Transmission fluid, or ATF (Automatic Transmission Fluid), is a lubricating fluid that is somewhat similar to engine oil. It goes (no surprises here) in the transmission to keep everything lubricated and working properly.

The first thing you should know about transmission fluid is completely trivial, but may shock you if you’ve never worked with the stuff before: it stinks! Like, really, really smells bad. The smell of transmission fluid could perhaps be compared to BO mixed with rotting food, and, due to its nature, if you get it on you, it ain’t coming off for a while. So, basically, don’t get any on you, or wear PPE when you’re working with it if you think that might happen.

It’s made up of many different additives and, although it may contain it to some degree, shouldn’t be considered as an oil. It’s used for lubrication, as a hydraulic fluid for clutch engagement, as a corrosion inhibitor. It must be compatible with all electrical components with low conductivity.
Transmission fluid is also dyed red. This allows you to gauge its condition. If, when you’re checking it, the red seems vibrant, there is no problem. But, if the color appears to be more burnt, then it’s time for a change.

Potential things to watch out for

Although you could have too much transmission fluid in your car, the more likely situation is that you will begin to run out. This will usually be due to slight leaks around the transmission.

Watch out for the following signs, as they may indicate a problem.

  • Vehicle lurches under gear changes.
  • A transmission fluid puddle underneath the car after it has been sat for a time.
  • Dashboard indicators. Modern cars will often have sensors wired into the transmission to let you know if the level is getting too low, or there’s a problem with the transmission of some kind.

What to do next

If one or more of these things seem to be happening to you while you’re driving, then there will be a problem of some kind with the transmission. This won’t necessarily be due to the level of transmission fluid being low, but you should hope it is – anything else may require a transmission rebuild, which would set you back a few thousand dollars.
Checking the transmission fluid level is a very simple task – we’ll walk you through it quickly now.

How to check the fluid level

  1. Make sure the car is parked on level ground. If the ground is sloped, then your readings will be skewed. Open the hood.
  2. Note that some newer cars measure the level of oil electronically. Everything’s electric these days! If this is the case, all you need to do is scroll through your dashboard until you find the transmission fluid level setting, which should let you know. You may need to consult your owner’s manual to find how to do this.
  3. Most cars, though, use the traditional dipstick approach. In the same way as to how you check your engine oil level, the dipstick shows the level of fluid in the transmission. It’s a crude yet very effective technique.
  4. Take a rag in one hand and pull the transmission fluid dipstick out using its handle. If you aren’t sure which one the transmission fluid dipstick is, consult your owner’s manual and look for a diagram of the engine bay.
  5. The dipstick should be coated with a translucent, red fluid. Using the rag, wipe it clean, and then put the dipstick back into its slot. Pull it out again, and look at it.
  6. The transmission fluid should be between the two marked points on the dipstick. If it’s too high, there is too much in there. If it’s below the bottom marking, there isn’t enough, and it’s time for a top-up or complete replacement.

If the transmission fluid looks a “burnt” color, or if it’s gone milky or has air bubbles in it, you are likely to need to take it to a specialist. Somehow, the transmission fluid has become contaminated. The cause of this needs to be fixed as soon as possible.

How to top up the transmission fluid

Firstly, make sure you have the right type of transmission fluid. This will probably be printed on the cap. Alternatively, you’ll find it in the owner’s manual or by looking up the vehicle information online. Using the wrong type of ATF could cause serious damage to your transmission.

You’ll also need a funnel.

  1. Take the transmission fluid and the funnel and go to the car, with the hood open and the dipstick removed.
  2. Put the funnel in the slot that the dipstick usually sits in and add a small amount of transmission fluid.
  3. After this, remove the funnel and the ATF and set them to one side. Use the dipstick to measure the level of fluid in the transmission.
  4. Keep on repeating this until the level is between the two markers.
  5. Start the car and run through all the gears, including neutral and reverse. This will allow the fluid to lubricate the whole system and give an accurate reading for you. Leave the engine to idle for a few minutes.
  6. Recheck the level of fluid, using the dipstick. It should still be within the two markers. If this is the case, you’re all done.

If the fluid level has dropped dramatically, you have a bigger and deeper problem than just old fluid. You’ll need a professional to look at it and, unfortunately, it’s not going to be cheap. If it has only dropped a little bit, simply top it up and repeat the process.

It’s highly recommended to continue checking the fluid level over the next few hundred miles you do. There may be a slow leak. Again, this will need to be looked at by a specialist if it is the case.


Checking and topping up your transmission fluid isn’t too tricky, and hopefully will save you a bit of money, instead of taking your car to an auto shop. We hope you found this article useful!

Ryan Kelly

Ryan Kelly has a keen eye for everything motorsport. An avid F1 follower and car enthusiast, his reporting and reviews shine through on GrandPrixTimes. With his years of experience of being in and around cars, his articles are second to none.

We are a team of ASE certified mechanics that have created this guide to help you save money while doing the job yourself, or at least see what you are paying for when having the job done at a shop. An automatic transmission or transaxle fluid dipstick handle is located toward the rear of the engine or near the transaxle. Checking and adding automatic transmissions fluid can vary depending on design and manufacturer, some newer vehicles will require a different approach. We will show you how to identify and perform each type below.

What Goes Wrong?

Often, a transmission problem can be as simple as low or dirty fluid. Checking fluid is not difficult and should be the first thing done when experiencing shifting issues, a delayed shift, or engagement issues. Allowing the transmission fluid to run low can cause a transmission to lose internal pressure which will result in the clutch packs or drum bands to slip causing the loss of clutch material. Many times this can lead to transmission failure which will warrant a transmission replacement or rebuild.

What’s the Cost?

Most shops will check your transmission fluid for free or as part of an engine oil change service if you have an external dip stick model, but if your car does not have a dipstick which manufacturers started doing on some models you will be charged up to .5 hours plus fluid to do the job at a shop.

Where is It?

Automatic transmission dipstick locations will vary, if you have a rear wheel drive vehicle the dipstick should be located near the firewall behind the engine on the left side (looking straight at the engine). On front wheel drive vehicles the dipstick will be near the transaxle itself. If you cannot locate the dipstick, the vehicle will need to be lifted and supported on jack stands to access the transmission pan or case.

Lets Jump In!

  1. Park the vehicle on a level surface and start the engine allowing it to idle. With the parking brake applied, place the shift lever in park, some older cars will need to be checked in neutral which it will say so on the dipstick. With your foot on the brake pedal, move the shift lever through each gear, pausing for about three seconds, position the shift lever back into park. Located the fluid level dipstick which should be toward the rear of the engine, (rear wheel drive).
    How to add transmission fluid
    Some dipsticks will be labeled with the type of fluid used or the updated equivalent, this one says Mercon 5 in small print.
    How to add transmission fluid
  2. Remove the dipstick and wipe clean using a paper or shop towel, typically a dipstick will be fairly long.
    How to add transmission fluid
  3. Return the dipstick so it is fully seated inside the tube, wait three seconds, and pull it back out again. This will show the level of the fluid inside the transmission. Check both sides of the dipstick to confirm the fluid level which must be in the crosshatched area above the minimum level indicator. If the fluid level is in the acceptable range, reinstall the dipstick and you are all set. If the fluid level is low, use a long-neck funnel to add only enough fluid to bring the level into the crosshatched area on the dipstick. Start by adding a 1/4 quart at a time, add enough fluid to bring it up to the proper level, do not overfill.
    How to add transmission fluid

Checking Transmission Fluid Without a Dipstick

On some newer vehicles there is not a traditional tube transmission dipstick to check the fluid level, condition or add fluid. There can be a “screw in” dipstick, a fluid level plug much like a standard transmission, or a level tube mounted in the bottom of the transmission fluid pan that is sealed with a plug. We will go over each of these types below. Follow the procedure above before checking the fluid level.

  1. With the engine at idle, raise the vehicle on a hoist or lift using a jack supported by jack stands. The vehicle must be level with transmission in park. Remove the dipstick plug with the level indicator attached. The image below has the fluid pan removed so you can see the level indicator. Unscrew the plug and proceed to check the fluid level in a normal manner. If fluid is needed a small fluid pump can be used which is about $10.00 (US) on Amazon.
    How to add transmission fluid
  2. Here you see innovation as our mechanic is using a squeeze bottle style of arrangement with a plastic tube attached to add fluid.
    How to add transmission fluid
  3. Remove the fluid level gauge from the fill plug, This will be used to measure the amount of fluid inside the transmission.
    How to add transmission fluid
  4. While the engine is still running insert the level gauge into the plug hole and remove, this will show the level of the fluid.
    How to add transmission fluid
  5. Reassemble the level gauge back into the plug and reinstall back into the transmission case and tighten, (5 foot pounds) and you are all set.
    How to add transmission fluid
  6. Here is an example of a side plug type which works in a similar manner. The side plug style is filled until it runs out then reinstall the plug, much like a differential or standard transmission fill plug, again the engine must be running. (Images courtesy of AllData)
    How to add transmission fluid
  7. This is the drain tube type. The fill tube style acts much like the side plug style, pump fluid in, then remove the fill tube and the excess with run out creating the correct fluid level, (if the fluid is flowing as a steady stream, wait until the fluid begins to drip before replacing the fill plug, if no fluid flows out, add fluid until fluid drips out). The fluid level height is achieved by the tube inside the transmission pan. (Images courtesy of AllData)
    How to add transmission fluid

Transmission Fluid Color

Transmission fluid color and odor are very informative when checking the fluid level. A portion of a transmission is basically a hydraulic pump which degrades the fluid properties making it less effective. If the fluid color is dark or black and has a burnt odor the transmission should be serviced. Transmission fluid that is the color of a pink milk shake is an indication of engine coolant mixing with the fluid. This is because the transmission cooler inside the radiator has failed, when this happens the radiator needs to be replaced and the transmission fluid changed.

Watch The Video!

This video shows a transmission service and refill which will show you how to check and add fluid.


Our certified technicians are ready to answer transmission fluid questions for free. We hope you saved money and learned from this guide. We are creating a full set of car repair guides. Please subscribe to our 2CarPros YouTube channel and check back often for new videos which are uploaded regularly.