Should the car be running when adding transmission fluid

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Locate the Dipstick
Transmission Fluid Tips and Maintenance
Signs of Low Transmission Fluid
Things to Look For When Checking Your Transmission Fluid
How Often Should You Check Transmission Fluid?

Locate the Dipstick

The transmission fluid dipstick looks like the engine oil dipstick. The location will depend on your vehicle. Here’s how to locate the dipstick:

Step 1:Leave the engine running and open the hood to your car. The car must be warm when you check transmission fluid.
Step 2:If you have an inline engine, look behind your oil dipstick, toward your windshield, to locate the transmission fluid dipstick.
Step 3: If you have a front-wheel drive vehicle, look to the right of your oil. The transmission fluid dipstick will likely be located near your car’s battery.

Safety Tip: Cars with a manual transmission must be raised on a hoist to access a special plug at the bottom of the vehicle. If you feel unsafe doing this on your own, or you do not have the proper equipment, consult a mechanic for guidance on how to check transmission oil.

Once you’ve located the dipstick, it’s time to assess your fluid levels. The process should take only a few minutes if you’re familiar with your vehicle. Here’s how to check transmission fluid:

Step 1: Remove the dipstick. Make sure the engine is running and your car is in park or neutral. The parking brake (also known as the emergency brake) should be on as well.
Step 2: Wear plastic gloves if you have sensitive skin. Touch the tip of the dipstick with your finger. Rub the fluid between your thumb and index finger, checking to see if the color is clean and clear/pink. Look for burnt particles or a dark color. If you notice burnt particles or a dark color, you should have your transmission fluid changed by a professional. If not, proceed to step three.
Step 3: Wipe the dipstick clean with a lint-free cloth and re-insert it back into the transmission fluid. Remove the dipstick again and check the level. The fluid should reach the “FULL” line. If not, add a small amount of transmission fluid at a time, checking to make sure you don’t overfill.

Transmission Fluid Tips and Maintenance

Maintain proper transmission fluid levels to keep your vehicle running smoothly. Here are a few tips to help preserve your car and transmission:

Checking transmission fluid levels can be more difficult depending on the make and model of your car. Consult your owner’s manual before performing any of the steps above.
Check levels at least once per year. Many mechanics will do this as part of a routine service. You can do this on your own more often as well to ensure optimal performance.
Many experts recommend changing your transmission fluid every 30,000 to 50,000 miles.

Signs of Low Transmission Fluid

Here are the common signs of low transmission fluid:

A burning smell inside or outside your car.
Grinding or vibrating when shifting gears.
The vehicle is shifting gears slowly or not accelerating properly.
The car feels rough, particularly when shifting gears or performing tasks like accelerating onto the freeway.

Learning how to check your transmission fluid is simple and will help you keep up with your car's maintenance while saving money on repairs. Make sure to check out The Home Depot's wide variety of transmission fluids to keep your car in great condition. Shop online today and find the right transmission fluid for your vehicle.

Your transmission is just as important as the engine in your vehicle. Without it, your car may be able to start but will go nowhere fast. Keeping your transmission in good condition is vital and as with any major component on your vehicle, protection begins with maintenance. Checking your transmission fluid levels, color, and even scent will help you understand what condition your transmission is in. Regular flushes and good habits such as using your parking brake when stopped and shifting to drive from reverse only at a complete stop are great ways to help extend the life of your transmission. Not sure how to check your transmission fluid? Follow our quick reference guide!

The transmission fluid dipstick is similar to the oil dipstick, while the oil dipstick measures the level of the car’s engine oil, transmission dipsticks measure the level of transmission fluid in your vehicle. Keep in mind many transmission troubles are due to low fluid levels. If the fluid is low, it is likely there is a leak and it will need to be found and repaired by a professional right away. If you need to add additional fluid, be careful not to overfill the reservoir. Overfilling transmission fluid can cause the fluid to foam, putting excess pressure on the transmission, and forcing fluid out of the vent or a seal. This can result in slipping and instability.

Park your car on a level surface and lift the hood.
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. Allow the engine to continue running while you check the level. Note: Honda is the only manufacturer that recommends you turn off the engine and then immediately check the level.
Locate your dipstick. Often found near the oil dipstick in front-wheel drive vehicles and near the rear of the engine for rear-wheel-drive engines, it is conveniently labeled for access and can have a red, pink, or yellow-colored handle.
Pull out the dipstick and using a clean rag, wipe it clean, and place it back into the reservoir. Remove the dipstick again and locate the indicators on the stick to determine whether the fluid is “full” or “low.” If the fluid is full, replace the dipstick and close the hood. If the fluid is low, take your vehicle to an auto center right away for a fill.

Things to Look For When Checking Your Transmission Fluid

Color – Most new transmission fluids should be a bright, transparent red color. Darker red or light brown is normal but reflects its age and usage. A darker brown color is an indication that fluid needs to be changed. Black is a bad sign, however. This means that the fluid is burnt as a result of some transmission troubles. Your vehicle should be taken to a transmission specialist to determine the cause of the burnt fluid, immediately.
Consistency – After some time fluid can appear thicker than usual. This is normal, but good transmission fluid should appear new. Additionally, fluid should not contain any contaminants or particles including metal shavings. Metal shavings could spell trouble and will need to be inspected right away. Foamy fluid could indicate either too much fluid is present, it is overheating, or the wrong fluid has been added.
Smell – Clean fluid is practically odorless, but if you notice something similar to burnt toast, it is cause for concern. A burnt smell is a sign that the transmission has developed problems and needs to be serviced by a professional right away.

NOTE: Many newer cars are not equipped with transmission dipsticks, making checking the transmission fluid at home impossible. In that case, an automotive repair professional will need to check the fluid level through a plug located on the side of the transmission or by checking the car’s internal computer.

How Often Should You Check Transmission Fluid?

Arizona has a hot, dry, and dusty climate defining it as a “severe driving climate.” In severe climates, vehicles require a little more TLC, meaning maintenance services should be performed on a more frequent basis. Transmission fluid flushes should be performed every 30,000 miles and transmission fluid levels should be checked, at least every six months. Now that you know how often to check your transmission fluid and the steps on how to do so, you’re one step closer to extending the life of your transmission!