2003 S500 (255,000 miles), 2015 ML350 4matic (66,000), 2009 S550 4matic (110,000)
Recently purchased and going through all systems ... changing fluids, filters, updates, etc. I have seen some information about someone attempting to change the front differential gear oil, but it was iffy at best. It appears to be done by removing one of the CV shafts for refill after draining from drain plug. I haven't looked yet, but is it possible to add gear oil through the breather port if it is even accessible? Maybe install a drain port to drain and fill ... quick connect? Anyone tried this yet?