I recommend going ahead and replacing the conductor plate and transmission connector while you are in there also.
Here is a kit from Amazon for $118 :
https://www.amazon.com/APDTY-Transmi...-benz%3Aslk320

You will also need 5 liters of fluid, this is what I used :
https://www.amazon.com/gp/product/B0..._rd_i=15724571

I used my topsider to suck out all the fluid, then marked the level with some tape on the outside of the topsider container so I could put back in exactly the amount I removed.
There will be a few ounces left in the pan when you remove it, add that to the topsider before marking the total level.

DO NOT USE THE tiny BOLT IN THE TRANSMISSION CONNECTOR TO TRY AND PULL THE CONNECTOR INTO SEATED POSITION, YOU WILL MOST LIKELY SNAP THE BOLT !!!!!!

There are uTube videos covering the entire procedure.

DISCLAIMER !!! I am a proactive kinda guy, I fix it before it fails. If you are a "if it ain't broke, don't fix it" type, just get a gasket, filter and the fluid.