The fluid is added through the dipstick hole while the engine is running. With the parking brake on and the brake pedal depressed, move the selector lever to all positions in turn. Finally, move the selector to position P and check the fluid level again.
Figure 343. Drain plug in the automatic transmission housing
Figure 344. Drain plug in the torque converter
To replace the working fluid, the old one must first be drained through two holes located in different places. The plug of one of them is located in the crankcase and is shown in the figure 343. The other one is screwed into the torque converter. To access it, you need to manually turn the engine crankshaft until the plug appears in the hole in the torque converter housing, as shown in the figure 344.
When replacing the working fluid, you must proceed as follows:
Article was obtained from the portal: mercedesman
- take the car for a short drive to warm up the liquid but not make it too hot;
- place the car on supports and place a container of approximately 6 liters under the gearbox;
- use a hex key to unscrew the plug from the drain hole in the gearbox housing and let the fluid drain. It is important that the liquid is not too hot. Touch the crankcase: if it is very hot, wait a while until you can touch the crankcase with your hand. After draining the liquid, check the plug sealing ring and replace if necessary. Then screw in the plug and tighten to 14 Nm;
- turn the engine crankshaft with the head on the crankshaft pulley bolt until the drain plug in the torque converter is accessible. Use a hex key to unscrew the plug and wait until the liquid drains. Then tighten the plug to 16 Nm. Replace the sealing ring if necessary;
- fill the gearbox with the recommended fluid. The above amount will not fit completely, as some of the old fluid remains in the box. Therefore, you should check the level with the dipstick from time to time. Finally, insert the dipstick and check the fluid level as described earlier.
