How To Check Transmission Fluid Without A Dipstick

Transmission fluid is a crucial part of how your vehicle drives, and contamination or low levels of transmission fluid can severely impact your car’s overall performance and transmission health. The automatic transmission in your vehicle is made up of a system of gears, valves, and clutches that help you shift, and these parts can wear out if they are not properly lubricated. Your car’s transmission requires occasional maintenance, as does any system that experiences constant heat and usage while on the road. Most modern vehicles with an automatic transmission are equipped with a transmission dipstick, although some late-model cars may not have a dipstick that allows you to easily check its fluid level at home. Transmissions that don’t include a factory dipstick are usually considered non-serviceable, except at a professional shop or the car dealership, and this can be frustrating to people that like to maintain their own cars. Though it can be concerning to open your hood and not see your transmission fluid dipstick, there are a few options that can allow you to check transmission fluid on your own without going to a dealership or shop.

When Should I Check My Transmission Fluid?

Just like maintaining your wheels, tires, and oil level, a vehicle’s transmission should be checked for proper fluid levels regularly to prevent any undue wear or damage that can be caused by the transmission’s constant shifting while driving. Transmission fluid helps lubricate and cool the internal components of an automatic transmission, helping your vehicle shift smoother while saving fuel and energy. It’s important to check your vehicle’s owners manual to determine if the transmission fluid even can or needs to be inspected, or the exact maintenance interval specified by the manufacturer. Generally, it’s recommended that you check and, if needed, replace transmission fluid in your vehicle every 50,000 to 100,000 miles. Vehicles that operate under high-stress conditions should have their transmission fluid level and condition checked more often. Inspecting transmission fluid not only tells you if you have the correct fluid levels for safe, effective transmission operation, but can also indicate if your transmission fluid is contaminated or burnt. Burnt transmission fluid is typically caused by a transmission malfunction and is a clear indicator that something is wrong in the internal transmission assembly. Flushing and replacing the fluid is often not enough to save your transmission if the fluid is already burnt, and it may be best to consult with a local transmission shop. Find an Automotive Service Professional Near You to determine the best course of action.

What If My Transmission Dipstick Is Missing?

A missing transmission dipstick can be an unhappy surprise if you planned on checking your fluid levels for the first time, but don’t worry–there are a number of solutions to help you determine how and if you should check your transmission fluid. Transmission dipsticks are located beneath the hood toward the back of the engine bay near the firewall in many cases, and are usually marked with a specific color or transmission symbol to help them be more easily identified. 

If you cannot find your transmission dipstick, it’s recommended that you check your car’s owners manual to learn more about your vehicle. Some newer vehicles do not have a transmission dipstick due to their lifetime sealed transmission, meaning they do not need frequent fluid maintenance or replacement. Even if your vehicle lacks a dipstick, it is possible that it will still need transmission fluid checks and flushes to ensure the longest transmission life. If you have determined that your vehicle needs transmission maintenance and does not have a transmission dipstick, don’t fret. O’Reilly Auto Parts has compiled an easy-to-follow list of instructions to help you check transmission fluid levels and condition. 

How To Check Transmission Fluid Without A Dipstick

Option One: Buy A Transmission Dipstick

If your vehicle has a transmission tube or service port located in the engine bay, you can easily check your transmission fluid levels by purchasing a transmission dipstick from O’Reilly Auto Parts. Your owners manual will detail if your vehicle has this port, and its exact location. Below we will detail a straightforward method of DIY transmission fluid inspection.

1. Park your vehicle on a flat, solid, level surface.
Avoiding having your car at an angle or slope can provide more accurate transmission fluid level readings. Once your vehicle is parked on a level surface, be sure to engage your parking brake to ensure the vehicle does not move during this process.

2. Start your vehicle.
Checking transmission fluid levels typically requires the vehicle to be at operating temperature, so it’s important to start and run your vehicle for approximately five minutes before you begin. This helps circulate fluid throughout the transmission and causes fluid temperatures to rise to appropriate levels. You should try to avoid checking your transmission fluid levels after driving since the engine will be hotter and the transmission may be at an above-average operating temperature, resulting in expanded fluid that can supply an incorrect reading. It’s important to know the exact transmission temperature detailed in your service manual, since this can impact the fluid levels if the engine is too hot or too cold. You can use a scan tool or a diagnostic scanning tool to help pinpoint the exact temperature of your transmission before beginning the rest of your repairs to ensure you are getting accurate fluid measurements, but these tools are often too costly for DIY mechanics and may require a professional shop.

3. Locate the transmission fluid dipstick port.
Usually this looks like a small tube with a screw-on lid, and the location of your transmission dipstick port can be found in your owners manual. Be sure to know its exact location before continuing to prevent damage to unrelated components or confusion under the hood.

4. Insert the transmission dipstick in the transmission dipstick port.
As you would do with an engine oil dipstick, place the transmission dipstick in the port and slowly maneuver it downward. If you feel metal-on-metal contact, you have gone far enough and should not continue to push, as doing so can damage your transmission pan.

5. Clean off the transmission dipstick.
Remove the dipstick from the transmission, and, using a shop towel, rag, or paper towel, clean off the transmission dipstick of any excess fluid. This helps ensure you get the most accurate reading of fluid levels.

6. Determine the correct fluid amount for your vehicle.
Using your owners manual, pinpoint the exact transmission fluid levels your vehicle calls for. You can then use this information to mark the correct fluid levels on the transmission dipstick to provide a point of reference. A permanent marker or metal shaver can be used to make lasting marks on your transmission dipstick to make future maintenance tasks a little easier. Keep in mind, in some cases fluid levels are dependent on temperature, so you may need to take some additional readings to determine where the marks should be placed. Once you’ve marked the ideal fill level, insert the dipstick again.

7. Re-insert transmission dipstick with marked levels.
Once you have the correct levels marked, insert the transmission dipstick again to get an accurate reading of fluid levels. If the fluid is on the dipstick and within the correct range, your transmission has enough fluid. If there is not enough fluid to reach the minimal levels, you should refill your transmission fluid using a funnel and the correct fluid specified by your manufacturer. You will want to repeat these steps until the fluid reaches the marked indicators on your transmission dipstick.

8. After you’ve determined your vehicle has enough transmission fluid, reinstall the transmission service cap.

Option Two: Use the Transmission Inspection Plug and Fill Plug

If you do not have access to a transmission dipstick or if your vehicle doesn’t have any provisions for measuring or filling the fluid levels, don’t worry, we have another solution. Again, it’s important to familiarize yourself with your vehicle and its service specifications, as well as protecting yourself with the proper safety gear and equipment to keep you safe during repairs.

1. Locate the transmission case and the inspection fill plugs. Threaded into the side or bottom of the transmission oil pan. You will be looking for two plugs threaded into the side or bottom of the transmission pan or case. There are usually two plugs located on the transmission: a fill plug that contains and seals the transmission fluid and also allows for fluid refills, and the inspection plug, which is usually located on the side of the transmission case and helps you determine fluid levels. The locations of these plugs vary by the year, make, and model of your vehicle, so it may be helpful to check your service manual to determine each plug’s exact location and the appropriate procedure.

2. Park your vehicle on a level, solid surface and let the engine idle. This can help ensure that the reading is as accurate as possible, as parking on a slope or uneven surface may affect the perceived levels. Ensure your car is in Park and let the engine idle.

3. Start and run your vehicle to reach normal operating temperature. In order to help move transmission fluid throughout the system, run your vehicle until the engine reaches proper operating temperature. The right temperature is crucial in getting a correct fluid reading during a DIY transmission fluid check. You can use a temperature scanning tool or a diagnostic scan tool to make it easier to pinpoint your vehicle’s temperature to tell when it is safe and effective to measure fluid levels. Since most manufacturers advise you should check your transmission fluid at a certain temperature, it’s important to check your owners manual to find this exact temperature range. Try to avoid getting your vehicle too hot, as this can cause the fluid to expand and provide an inaccurate reading.

4. If needed, jack up your vehicle. Using a jack stand for each wheel, jack up your vehicle until you can access the transmission case that is located on the undercarriage. If you drive a larger SUV, truck, or another vehicle with considerable ground clearance, you may be able to skip this step, but most passenger cars will require the vehicle to be raised. It's usually a good idea to lift and support each end of the vehicle to keep it level and prevent inaccurate transmission fluid readings. It’s advised you turn off your vehicle during this step to ensure not only your safety, but that your vehicle does not get too hot.

5. Place a drain pan beneath the inspection plug and loosen it. With an oil drain pan located beneath your transmission case, use a wrench to begin loosening the inspection plug. Make sure you're wearing protective gloves to avoid being burned by the hot fluid and plug before loosening and removing the inspection plug. Once the plug is loose, ensure you’re wearing protective gloves to avoid being burned by the hot fluid or plug, and remove the plug.

6. Watch for fluid drainage. This is a great time to visually inspect your fluid for changes in color (dark brown or black), viscosity, and scent, which can pinpoint old, burned, or contaminated fluid that requires a transmission fluid flush or transmission repair. If you notice fluid is trickling out from the inspection plug, this is a sign that your transmission was overfilled to begin with. If this is the case, wait until the transmission fluid has stopped draining and move to Step 7. If you do not see any fluid draining from the inspection plug, you can remove the fill plug in Step 8.

7. Reinstall the inspection plug. Once the fluid has stopped draining out of the inspection plug, be sure to reinstall the inspection plug correctly to avoid transmission fluid leaks. If your vehicle does not need more transmission fluid, your maintenance task is done.

8. Remove the fill plug. The fill plug, usually located on the side or top of the transmission case, allows you to easily fill or top off fluid levels. Since you are ready to add more transmission fluid, use a funnel or long hose to slowly add small amounts of transmission fluid into the fill plug opening.

9. Watch the inspection plug for drainage. Continue adding transmission fluid to the fill plug hole, and continually check the inspection plug for signs of draining or overflowing fluid. Once you see transmission fluid exiting the inspection plug hold, this is a sign that your transmission fluid is at the right level and you should not add any more to prevent overfilling. If you do not see fluid coming from the inspection plug, continue filling fluid until this happens.

10. Reinstall the inspection plug and fill plug. Once you’ve determined the transmission fluid level is appropriate, it’s time to reinstall the inspection and fill plugs. Be sure to torque the plugs to your manufacturer’s specifications to prevent transmission leaks and subsequent performance issues.

When Should I Change Transmission Fluid?

Driving with dirty, contaminated, or old transmission fluid can severely impact the performance and overall health of your transmission. If your vehicle’s transmission fluid has an inappropriate consistency, is burnt or worn out, or has contaminants such as metal shavings, the fluid will be unable to properly lubricate and cool the internal components of the transmission. This issue can cause harm to your transmission's gears, valve body, and more, and could make shifting more difficult. This can impact driveability, fuel economy, and vehicle health.

Symptoms of Bad or Low Transmission Fluid

Signs of transmission fluid that should be replaced or topped off include:
• Dark red or brown fluid color
• Slight burning smell
• Whining sounds
• Vehicle does not move or requires more power to begin moving from a stop
• Slipping gears while shifting
• Excessive transmission temperatures, which can trigger a Check Engine light or Transmission Temperature light
• Grinding noises
• Metal shavings in transmission fluid
• Fluid leaks seen beneath the vehicle


If you notice any of the signs of bad transmission fluid listed above, or if you have exceeded your vehicle’s maintenance intervals, it’s important to inspect and replace your transmission fluid to ensure it's in the best condition for operation. Your manufacturer may specify that the transmission be flushed or otherwise serviced at a specific mileage. Find the parts, fluids, and safety items you may need to check transmission fluid safely and effectively both online or at an O’Reilly store near you, so you can get the job done right the first time.

Find The Transmission Repair Parts You Need At O’Reilly Auto Parts

Maintain a healthy transmission for miles to come by performing proper transmission inspection and fluid maintenance. O’Reilly Auto Parts stocks replacement transmission dipsticks and tubes, as well as transmission dipsticks for Chrysler 300s, Honda Accords, Nissan Altimas, Ford F-150s, and many more to help you manually check your transmission fluid on vehicles without a dipstick. If your vehicle is equipped with a transmission dipstick, read our helpful article on how to check and fill transmission fluid to keep your transmission performing as it should. Don’t forget after you’ve completed your transmission service that O’Reilly will recycle your used motor oil, transmission fluid and more for free in-store. Need more repair or maintenance assistance? Visit our helpful How-To Hub for informational videos and articles on how to best care for and repair your car.

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