Gearbox oil, you might want to proactively change it ...

I'm the resident loudmouth for oil and gearbox stuff so I'll give you my $0.02.

You should be able to find Hyundia's 70W DCT at the dealer or order Redline MT-LV online, 1 litre or 1 qt is enough (only just). There are other DCT/DSG oils that might be locally available as well. Automated manual transmissions use thin oil to allow fast shifting. Around 5 cSt @100°C and GL4 is what we need.

But another option for the extreme cold is an ATF-ULV which I'd bet is off the shelf in your area. ATFs have a suitable GL4 gear rating and viscosity. Some low-temp Kona/Niro owners mention a whine when cold which is the result of oil being a bit too thick. I even get this at 7°C with the 70W-75 that I use, 7.5 cSt. The Hyundai oil is 5.4 cSt @100°C while a ATF-ULV is around 4.5.

But don't use a 75W-90 or anything close, they're way too thick. The high motor speed requires a thin oil.

 

Yes, best stick with the 70W.

 

Locally a Kona owner was quoted NZ$446 for the pleasure, a blantant ripoff. Others pay NZ$130 upwards, many at around 200. In the US the only report I have is US$140, in SoCal.

I'll note that the oil called out in the owner's manual of either EV is Hyundai/Kia DCT 70W GL-4 which the SDS describes as "clear brown". It doesn't say anywhere to throw in a pinch of iron and aluminium filings, which is what 99.9% of all these cars are running right now. So, yes, changing the oil at least once is a really good idea to reduce the risk of unnecessary gearbox noise, be it a warrantable repair or not, never mind the admittedly-rare chance of a complete failure.

The gearbox is not a cement mixer, it's a precision machine and needs pristine oil as stated. Compounding this problem is that there is considerable evidence that the internal magnet that MOBIS/Transgear install for the sole purpose of sequestering newly-released steel wear particles is not very effective. Many of us in Kona-land install either a magnetic plug or add a few magnets to the outside of the OEM plug, and by the two UOA reports so far, that's working. See the text in my video below.

Eleven Kona/Niro owners so far have paid for used oil analysis reports which I add to a graph for comparison as they roll in. Most first-time reports indicate the levels are "very high" for the kms/miles driven. And why is the oil black? That's been a quandary for me but I think it's mostly or only the aluminium contamination, the source of that being unproven so far.

 

The trendlines are more to indicate the data averages for comparison purposes rather than to imply that the levels increase linearly with distance driven, which they are unlikely to do. The data is far more widely scattered than I would have expected a year ago, which is puzzling given that every gearbox should be nearly identical. The number should ideally all be where JohnL's numbers are (near the 40,000 label), low, as we would see from a Nissan Leaf which has a similar gearbox design.

The aluminium contamination is not a direct threat to gearbox health but the fact that the source is unknown is troubling. There are no normally-wearing aluminium parts in this gearbox. The material must be coming off the housing, but where and why is the question.

My suggestions are outlined in the text of the video (which unlike here I can edit when needed) but I'll summarize the options, from least desirable to most:

1. Do nothing. Still a very low risk of anything going catastrophically wrong but I'd expect gearbox noise to become slightly more noticeable in most cases.
2. Do one oil change. That will clear out break in particles and lessen ongoing unnecessary wear but new iron wear particles will enter the oil and circulate.
3. Do one oil change and add a magnetic plug. New iron wear particles will be removed from circulation.
4. Do one oil change, add a magnetic plug then do further oil changes at some arbitrary interval ongoing, say 30,000 km or even longer.

Because I DIY the job and am still researching this deficiency, I'll pull the oil out every few thousand kms for inspection. Twice now I've simply filtered it and put it back in. My next inspection is upcoming and I expect the oil to be free of iron (magnetic plug installed) but tinted slightly due to the aluminium. I haven't had a UOA done as it's less convenient and more expensive here in NZ.

 

That inspection at 24,000 km last week resulted in an oil change after only 4,000 km because it was annoyingly totally black. There was not too much glitter, just a perceptible sheen at a close look. The magnetic plugs were virtually clean but they had been wiped clean only 1,000 km before at an inspection.

My current focus (on my Kona) is the OEM ceramic magnet which is only captured loosely by the gearbox housing directly under where oil is thrown off the final drive gear. The theory I'm pursuing is that the small magnet is spinning and fluttering due to the oil impingement being asymmetric, a bit like a water Pelton wheel. There has been evidence in one case where the disc magnet showed signs of wear at the edges which could be also generating aluminium debris off the housing. I think I can detect movement of the magnet while driving with a coil of wire placed near the magnet and an oscilloscope and will be carrying out that test in a few days.

 

For what it's worth I'm pretty sure I've determined why in most cases the oil quickly becomes black and contaminated after a year of chasing this. My last oil change at 24,000 km was for only 4,000 km duration and it came out black. So I jerry-rigged an inspection camera with an added LED to check out the internal magnet.
It's installed loose and I believe as a result will spin and rattle under the oil stream coming off the final drive gear. Any ferrous particles that stick to it will be scraped off plus it's likely to be wearing the aluminium features that hold it in place. I glued some magnets underneath to attempt to hold it in place for the next drain interval. The video is silent, sorry, but at least you can see what's going on. Background info is in the video description.
As a reminder, the Kona and Niro gearboxes are nearly identical other than a slightly different gear ratio.

 

Just FYI, yesterday I stumbled across a teardown video of a Niro EV gearbox which was noisy. In a nutshell the Ukrainian mechanic found that a steel cap (like a freeze plug) had fallen off the tail end of the input shaft. This is very likely the source of the infamous knocking noise, although it remains a mystery as to how that could lead to needing replacement of the motor, as commonly reported by owners of the Niro and Kona who have undergone repairs under the TSB process.

Also, I condensed my own video revealing the loose internal magnet down to 90 seconds.