I recently performed the AT fluid and filter change on our 2016 C300 with 33k miles - checked here for a thread but didn't see any so wanted to share a few thought on how the experience differed from doing the job on our 2008 GL. While this thread is for the GL it is helpful: Transmission Pan Bolt Torque Specs
- Beginning with the obvious, Mercedes updated the fluid around 2010 so it is now blue/green rather than red.
- The pan came off more easily though make sure you cut the two zip ties holding the wire to the pan prior to loosening the bolts. I tilted the pan down at the front of the vehicle first and managed to get all the remaining fluid into my catch pan with no spills.
- Draining the Torque Converter (TC) is more difficult because the access port is on the side of the housing rather than the bottom. Accessing it is easy from a clearance perspective, but the fluid drains into the housing rather than coming out the access port and then dripped out slowly. I didn't want to deal with the cleanup so stuck the rigid hose that came with my Mighty Vac fluid dispensing system (outer diameter ~9/32 or ~7.25mm) into the drain hole so that I could direct the fluid into my pan and that worked well with no leakage. its possible there is a tool made for this purpose that would thread into the TC drain but the hose worked well for me. Then to clean-up the bit that did drip into the housing I sprayed simple green in the port (once the bolt was reinstalled) followed by water which ran clear fairly quickly.
- Refill capacity was significantly more than expected. Mercedes says 6 liters if you drain the pan and TC but I refilled a total of 8.2 liters (9 minus 0.8 flow back). I suspect the coolant lines drained too which is a good thing in my opinion. Just buy 9 liters if you plan to drain the TC.
- Avoid the aftermarket stretch torque pan bolts that come in kits from Pelican - I snapped one on each job getting to the 4nm +180 degrees so I don't think it was something I did. The replacement Mercedes bolts worked perfectly. Next time I'll do the job with Mercedes gaskets and bolts the first time.
- The old fluid still looked pretty good - it was still blue though the single magnet and bottom of pan had lots of sludge on them. I put two more magnets that came with the Pelican kit into the pan