BEV E-Motor transmission/differential Oil - change?

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Just changed my gearbox oil today while doing the motor mounts.
My 2014 BEV got 96kkm on it, so about 60kmiles. The oil I've drained was about 0.5liters, looked filthy, and there was a spectacular formation of magnetic "paste" of gear pixie powder on the drain plug magnet. The good news was however it had no solid chips or shavings in it, just the finely ground metallic powder.
I've gone the easy way, and refilled with 0.5L of 75w80 BMW GL4 oil through the vent hole. It was a very easy affair.

This is the latest video I've found on this subject...good one.

These are the list of items used: @4:02

BTW...for anyone who's done it...did you see any noticeable difference after the oil change?
Bumping this thread for updates. Thanks!

- Is the Liqui Moly a superior oil to the OEM oil?
- has anyone seen a noticeable change after changing the oil?

OK how do you perform this procedure with a REX? I would think the breather would not be very accessible. What is the dimensions of the drain plug ...M12 x 1.5 or? My 2020 i3S with REX has no filler plug and I have seen a YouTube video where he changes the fluid uses the drain plug orifice only. Tricky.
M16x1.5. There's another thread about doing the rex. It's titled "Transmission oil change on a Rex from 2016 onwards".

If you have a later model Rex, the only fill options are though the drain plug or removing the axle.
What is the size of the drain plug? M22 x 1.5 or M16 x 1.5. I have conflicting information. The 2014 to 2018 models years have a fill plug and then BMW removed the fill plug in later years. But I think my 2020 i3 has the smaller M16 x 1.5.
This is my setup for my tranny oil change. M16 x 1.5 to 1/8 NPT with a 3 ft length of silicone tubing #18.

2020 BMW i3S


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