How to Check Automatic Transmission Fluid Level Mercedes Benz

How to check the transmission fluid level on your Mercedes Benz? You have come to the right place. If you were wondering, a low fluid transmission could show the same symptoms as a defective transmission. The transmission will slip or get stuck in gear when it is low on fluid. When the transmission gets stuck in gear is called the limp mode. If you have problems with your transmission, you first need to check the fluid level. Don’t spend money on anything, even transmission diagnosis, before you check the transmission oil level.

You will need a special transmission dipstick to check the transmission fluid level in a Mercedes-Benz. Mercedes Benz cars don’t come with a transmission dipstick. Don’t worry; you can get Transmission Fluid Dipstick 140589152100 for your Mercedes Benz on Amazon for under $20 and free shipping.

PMD Products Compatible with Repair and Replace of Mercedes Benz 722.6 Automatic Transmission Fluid Dipstick 1220mm 140589152100

Price Disclaimer

Instructions on how to check transmission fluid on a Mercedes Benz. Step by step with pictures and video.

1. Warm up the car. To measure the transmission fluid correctly, the temperature must be at least 80 degrees Celsius. To get the transmission to that temperature, you must drive the car for 15 minutes before you check the fluid. The best way to make sure your fluid has reached the required temperature is to use a Etekcity Lasergrip 774 Non-contact Digital Laser IR Infrared Thermometer Temperature Gun, Yellow/Black and point at the transmission oil pan. If you don’t want to drive the car, you can let it sit running for about 25 min for the transmission oil to reach 80 degrees Celsius.
   We are assuming there is at least some oil in the transmission. Verify there is oil in the transmission before you start the car or the warm-up procedure. 
2. Open the hood. 
   
3. Pull the air ducts that connect to the engine cover. Grab the engine cover on both sides and pull it straight up. It is held in place with 4 clips.  
   
4. Remove the engine cover. You only need to grab the cover on both sides and lift it up. It’s held in place with 4 clips only: no screws or bolts. 
   
5. Locate the transmission fill tube. It is located between the firewall and the engine. It is hidden, so look carefully. Be careful not to mistake the engine oil tube for the transmission tube.
   
6. Remove the transmission fill tube cap. First, you will need to brake off the transmission red lock pin. This is what it looks like. You must brake off the red lock pin before pulling out the black cap you see below. If you don’t have the red lock pin, that means someone had checked the fluid before and didn’t install the red lock pin.  
   

   Mercedes-Benz Transmission Dipstick Filler Cap + Lock Pin Genuine OE 10055/00091

   Price: $11.82

   

   Price Disclaimer
7. Place the car in R or D. You can place the shifter in the reverse or drive position.  Make sure to press the parking/emergency brakes. We prefer to put the car in reverse. It would be wise to have someone stay in the car and hold the brakes while you check the fluid level or place some block behind the wheel. You don’t want to rely on the parking brakes only.
8. Measure the transmission fluid level. See the video below.
   
   
   The transmission dipstick should show a level between the low and high 80-degree mark.
9. Add Mercedes-Benz-approved transmission fluid. If you find out that you are low in fluid, then add some. You add fluid through the tube you used to check the transmission fluid level. You want to add the Mercedes Benz Approved  Automatic Transmission Fluid 236.14 for use with the 5-Speed 722.6 & 7-Speed 722.9 Transmission. Mercedes part# 001 989 68 03 13
   

   Mercedes 722.6xx 722.9xx Auto Transmission Fluid (1 Liter) HIGH Performance

   Price: $33.37 ($0.99 / Fl Oz)

   

   Price Disclaimer
10. Check the level again. You want to double-check the fluid level. If you must add fluid, you must check the level again. You don’t want to overfill the transmission fluid level, which could cause shifting issues. If you accidentally added more transmission oil than you should have, you can use a 12V Fluid Oil Extractor Scavenge Suction Transfer Pump w/ Hose
11. Install the transmission tube cap and red lock pin. If your level is fine, install the cap and the red lock pin. Since you had to break the red lock pin off, you must replace it with a new one. They are only a few dollars on Amazon.
    

    Dorman 917-299 Transmission Filler Cap Lock Pin Compatible with Select Dodge / Freightliner / Mercedes-Benz Models, 5 Pack, Black

    Price: $8.55 ($1.71 / Count)

    You Save: $5.09 (37%)

    

    Price Disclaimer
12. Install the engine cover back on.
13. That’s it. DONE!