KiwiME
Member
A couple of us Kona owners have been working over the last two months to rectify a choice by Hyundai to not provide basic ferrous particle filtration in the gear reducer, or what everyone knows as a magnetic drain plug. All the Hyundai/Kia cars I've listed in the subject line I believe use the same family of gearboxes or even the exact same model as the Kona. It's a splash-lubricated 2-stage parallel shaft single-speed reducer with helical gears - that happens to be identical to the type used in the Nissan Leaf, hence the post in this forum. It runs a 70W/75W GL-4 such as Redline MT-LV, rather than an ATF.
Due to this inexplicable omission steel particles shed during break-in and from ongoing wear continually circulate among the gears and bearings until they have been ground down to a fine dust. This makes the oil look black like black coffee. For those not aware, rolling element bearings deteriorate faster when ingesting steel particles. Gears are less fussy but it's never a good thing.
So, our earliest oil change was done at 3,700 km and it was black with silver particles. We have reports of perhaps six more oil changes up to perhaps 80,000 km, and of course all were pitch black.
The simplest and cheapest preventative measure any owner can take is get ONE oil change ASAP before the callout in the maintenance schedule, typically 120,000 km. That will reduce the rate of ongoing wear from that point on and may lessen the chances of a failure outside of warranty. As many of us Kona/Niro owners know, there have been many gearbox noise complaints and a couple of documented catastrophic failures where the output shaft (diff) tapered-rollers fail.
The ideal situation is to install a magnetic drain plug (or 2 as used in the Leaf) when the car is new so that break-in particles can be sequestered up-front. Once these particles are ground down they have less affinity for the magnet and the damage has already been done. We are testing an aftermarket plug with a glued magnetic but I'd be cautious about recommending this one until I've had a few months more experience. There are others, some with a crimped-in magnet (like the Leaf) but they need to be short, not sticking out like on the Leaf. The thread is M18x1.5 and the thread length is 12mm. You could have 3mm more for the magnet to stick out. The washer is soft aluminium, 1.5 or 2mm thick.
We also have two oil analyses but there's nothing unexpected except the high aluminium and silicon levels, much as seen in the Leaf Blackstone reports posted elsewhere. The aluminium is a concern because of where that could come from, the primary and intermediate shaft bearing retaining diameters.
I'm an M.E. and have some industrial gearbox experience from long ago. I'm quite aware that these gear reducers can survive with oil in a deteriorated state but I'm puzzled that Hyundai/Kia would have taken such a risk when every other EV manufacturer seems to have done it right.
Due to this inexplicable omission steel particles shed during break-in and from ongoing wear continually circulate among the gears and bearings until they have been ground down to a fine dust. This makes the oil look black like black coffee. For those not aware, rolling element bearings deteriorate faster when ingesting steel particles. Gears are less fussy but it's never a good thing.
So, our earliest oil change was done at 3,700 km and it was black with silver particles. We have reports of perhaps six more oil changes up to perhaps 80,000 km, and of course all were pitch black.
The simplest and cheapest preventative measure any owner can take is get ONE oil change ASAP before the callout in the maintenance schedule, typically 120,000 km. That will reduce the rate of ongoing wear from that point on and may lessen the chances of a failure outside of warranty. As many of us Kona/Niro owners know, there have been many gearbox noise complaints and a couple of documented catastrophic failures where the output shaft (diff) tapered-rollers fail.
The ideal situation is to install a magnetic drain plug (or 2 as used in the Leaf) when the car is new so that break-in particles can be sequestered up-front. Once these particles are ground down they have less affinity for the magnet and the damage has already been done. We are testing an aftermarket plug with a glued magnetic but I'd be cautious about recommending this one until I've had a few months more experience. There are others, some with a crimped-in magnet (like the Leaf) but they need to be short, not sticking out like on the Leaf. The thread is M18x1.5 and the thread length is 12mm. You could have 3mm more for the magnet to stick out. The washer is soft aluminium, 1.5 or 2mm thick.
We also have two oil analyses but there's nothing unexpected except the high aluminium and silicon levels, much as seen in the Leaf Blackstone reports posted elsewhere. The aluminium is a concern because of where that could come from, the primary and intermediate shaft bearing retaining diameters.
I'm an M.E. and have some industrial gearbox experience from long ago. I'm quite aware that these gear reducers can survive with oil in a deteriorated state but I'm puzzled that Hyundai/Kia would have taken such a risk when every other EV manufacturer seems to have done it right.
