Kiwi_ME
Thread starter
Just to close off this thread for those interested, I recently discovered that the most likely reason for the black oil and high iron/aluminium UOA levels is that the gearbox internal magnet is loosely captive in the aluminium housing directly under the stream of oil off the final drive gear. It's clearly spinning and rattling, wearing both the aluminium housing and scraping off any particles it happened to catch. Internal magnets must be rigidly held due to the severe turbulence in the oil circulation happening in a small gear reducer. Nisson got it right with the Leaf.
I note that the Ioniq 5 / EV6 has a similar arrangement but also adds a filtered and pumped oil system to cool the electric motor. If that magnet has the same issue that filter could clog with shed particles over time.
Aside from what I found in the video, the near-absence of particle accumulation on a non-serviceable magnet after 24,000 km is good evidence of this theory. I've glued some neodymium magnets to the outside in an attempt to bias the internal magnet away from the "nib" that it's rubbing against.
In 2,000-4,000 km I'll check the oil again and see if it's clear this time.
I note that the Ioniq 5 / EV6 has a similar arrangement but also adds a filtered and pumped oil system to cool the electric motor. If that magnet has the same issue that filter could clog with shed particles over time.
Aside from what I found in the video, the near-absence of particle accumulation on a non-serviceable magnet after 24,000 km is good evidence of this theory. I've glued some neodymium magnets to the outside in an attempt to bias the internal magnet away from the "nib" that it's rubbing against.
In 2,000-4,000 km I'll check the oil again and see if it's clear this time.