How To: Reduction Gear Oil Change

[Dala]

I did a step-by-step video on this subject a few days ago when I did this on my ZE0

https://youtu.be/xQda4531plQ

[Learjet]

what about the dissimilar metal corrosion...using the copper washer on aluminum?

[Dala]

what about the dissimilar metal corrosion...using the copper washer on aluminum?

Yes! Aluminium and copper in contact will experience slight galvanic corrosion. How much depends on how often it gets wet/whether it is in salt water etc. Since the Leaf motor compartment is covered with protective plastic, you should be fine. But Alu is the correct replacement indeed!

When the other 60k miles rolls in, I'll be inspecting and chugging on some alu washers if needed.

[viso0103]

I did a step-by-step video on this subject a few days ago when I did this on my ZE0

https://youtu.be/xQda4531plQ

Hi, I also changed the oil , I wasn’t happy when I saw the magnets , 2013 USA leaf with 65Tkm

https://www.youtube.com/watch?v=KFV4Kcrs8Xc

https://www.youtube.com/watch?v=zK9zFqjW3P4

https://www.youtube.com/watch?v=RVsAxV6MVQc

oil change:

https://www.youtube.com/watch?v=0FoZJnP7oDk

[RajGiandeep]

Did this tonight, used the Redline D6 ATF. Noticed a difference on the way home. Seemed to take less power to stay at cruising speed. Happy I did it. Thank you for the videos & photos. Gave me the confidence to jump in there as do it. Very simple process. I'll do it again in another 30-40K miles. Seems like this is the first time it's been done at 51K.

[bobkart]

Did this tonight, used the Redline D6 ATF. Noticed a difference on the way home. Seemed to take less power to stay at cruising speed. Happy I did it. Thank you for the videos & photos. Gave me the confidence to jump in there as do it. Very simple process. I'll do it again in another 30-40K miles. Seems like this is the first time it's been done at 51K.

I change mine last week, at a little past 25K miles, using the Redline D6 ATF. I also sensed less power needed for the same speed, but it's difficult to be sure, as rain and air temperatures probably have a larger effect on efficiency, and both of those changed for the worse here around the same time.

I had less metal filings on my lower plug than I see in most of the pictures in this thread, but my fluid was more brown than red. Hopefully the synthetic fluid holds up better.

To follow-up on the earlier discussion about the third opening, I was able to fill using that opening and avoid removing the wheel, making the operation easier, as I was on ramps to access the bottom tray for removal (car was still level though), and would have needed a jackstand if that wheel would have had to come off.

(I suspect the middle opening could still be used to fill without removing the wheel, you'd just need a longer funnel with a flexible spout.)

[voltamps]

Has anyone tried AMSOIL Signature Fuel Efficient ATF? It says that it is Matic S equivalent. https://www.amsoil.com/shop/by-product/ ... ion-fluid/

Yep, that's the one I just put in. Had to buy 2 quarts, and it comes in those tooth paste type tubes, flexible, squeezable with a narrow spout to squirt in the fill plug. I didn't have to use a hose and funnel it in. Just crawled underneath, safely supported (jack stands or ramps, levelled), and the Amsoil unique bottle contorted right in. It's mostly PAO GroupIV and known to last a very long time.

You can choose about any ATF, preferably one that says "synthetic" somewhere on it, and in the "Dexron VI"-class. Dexron HP works too. Nissan Matic S of course is great. Redline D6 or the Amsoil Fuel Efficient ATF are likely the best, longest lasting, but Dexron HP is very close. Valvoline Maxlife Synthetic ATF is very good as well. Mercon LV acceptable.

Watch the youtube video posted earlier. Support your car safely (jack stands and/or ramps, levelled).
I torqued the drain and fill magnetic plugs to 25 ft lbs.
Get cheap aluminum or copper crush washers to replace the old ones.

My Leaf is very new, only 1,740 miles, & I was curious about how much iron particles might be on the magnetic plugs. Plus I wanted to get the GroupIV based ATF in there to get a "sealed-for-life" status that Nissan says we already had with the OE Matic S from mile 1. ....

In the picture below, notice the iron dendrites, whose tips continuously get shed in the oil flow to crunch into the gear teeth to some extent.

Also, earlier in this thread, somebody else's Blackstone report showed a lot of iron suspended in the ATF fluid (120 ppm is high) at around 60k miles.
Gear teeth surface wear-in (break in) mostly happens in the first thousand miles out of the factory. After that there should be a lot less iron worn off.

Picture is of a '20 Leaf with only 1,740 miles! Enough metal there to make the Brooklyn Bridge. (OK, a very tiny scale one.)



I drained & filled all from under the car after removing the plastic under-shield. Easy to reach plugs.

[voltamps]

This result prompts me to ask, "What fluid did you use?" OEM? Aftermarket?
My plan is to use AMSOil ATF Fuel-Efficient. I'm assuming that it has a slightly lower viscosity than the regular ATF.

Amsoil is slightly thicker when hot, but probably doesn't thicken up as much as a lot of ATF choices, like Matic S, in winter conditions.

OE Matic S kv100 = 5.4 cSt
"Amsoil Signature Series Fuel-Efficient Synthetic Automatic Transmission Fluid (ATL)" kv100 = 6.3
It's not enough diff to matter much, and that's viscosity at 100C (212F), & our gearbox probably won't get above around 180F on a hot day, hiway travel, so the viscosity difference is even smaller than a mere 0.9 cSt anyway.

[Precise1]

Has anyone tried AMSOIL Signature Fuel Efficient ATF? It says that it is Matic S equivalent. https://www.amsoil.com/shop/by-product/ ... ion-fluid/

Yep, that's the one I just put in. Had to buy 2 quarts, and it comes in those tooth paste type tubes, flexible, squeezable with a narrow spout to squirt in the fill plug. I didn't have to use a hose and funnel it in. Just crawled underneath, safely supported (jack stands or ramps, levelled), and the Amsoil unique bottle contorted right in. It's mostly PAO GroupIV and known to last a very long time.

You can choose about any ATF, preferably one that says "synthetic" somewhere on it, and in the "Dexron VI"-class. Dexron HP works too. Nissan Matic S of course is great. Redline D6 or the Amsoil Fuel Efficient ATF are likely the best, longest lasting, but Dexron HP is very close. Valvoline Maxlife Synthetic ATF is very good as well. Mercon LV acceptable.

Watch the youtube video posted earlier. Support your car safely (jack stands and/or ramps, levelled).
I torqued the drain and fill magnetic plugs to 25 ft lbs.
Get cheap aluminum or copper crush washers to replace the old ones.

My Leaf is very new, only 1,740 miles, & I was curious about how much iron particles might be on the magnetic plugs. Plus I wanted to get the GroupIV based ATF in there to get a "sealed-for-life" status that Nissan says we already had with the OE Matic S from mile 1. ....

In the picture below, notice the iron dendrites, whose tips continuously get shed in the oil flow to crunch into the gear teeth to some extent.

Also, earlier in this thread, somebody else's Blackstone report showed a lot of iron suspended in the ATF fluid (120 ppm is high) at around 60k miles.
Gear teeth surface wear-in (break in) mostly happens in the first thousand miles out of the factory. After that there should be a lot less iron worn off.

Picture is of a '20 Leaf with only 1,740 miles! Enough metal there to make the Brooklyn Bridge. (OK, a very tiny scale one.)



I drained & filled all from under the car after removing the plastic under-shield. Easy to reach plugs.

An old trick is to put a magnet into the drain hole so you simply have that much more magnetic surface area, but it is best if the pan is iron as well, for adhesion.
That said, I have drained a few Leaf gear boxes, and most of them are nasty. It is like transfer cases or differentials, most people never even consider it, but I haven't seen what I would consider "terrible" fines on the magnet. Maybe 2-3x of yours, but one of them was claiming 80k miles, so not bad considering.

And you are right about the majority of the wear being in the first "few" miles... one of the reasons the first oil change for a new car should be at 200-500 miles.

[voltamps]

An old trick is to put a magnet into the drain hole so you simply have that much more magnetic surface area, but it is best if the pan is iron as well, for adhesion.

A concern is if a magnet inserted would somehow get pushed up into the gear teeth (ouch!!) or on the side of a steel gear, imbalancing it. On the Chevy Bolt, they keep their internal magnet stuck to an oil baffle, right next to a big helical gear, and it could break free eventually. I prefer the Leaf's way of embedding 2 large magnets fixed securely to the drain plugs. My '19 Tiguan's Aisin auto tranny's magnet just sticks to the pan inside, prevented from "walking" around the pan (vibration over time) by small indentations, for comparison. To clean a Bolt or Tiguan magnet means you have to take off some large pieces, another advantage to the Leaf's drain plug magnets!

Ford Focus Electric & the Leaf both have no oil pump, no cooling circuit, no filter inside. ........ By comparison, GM made the oil system surrounding it's Bolt reduction gears complicated, with a gerotor oil pump, a huge transmission fluid filter, and a non-reachable magnet inside. .... https://cleantechnica.com/2019/12/25/bo ... deep-dive/

I prefer the simpler Ford & Nissan designs, easy to service, clean the magnets, not difficult. .. With the Bolt, it still looks easy to at least drain most of the fluid out and replace it but forget servicing the filter & magnet with any ease (sealed for life there.

That said, I have drained a few Leaf gear boxes, and most of them are nasty. It is like transfer cases or differentials, most people never even consider it, but I haven't seen what I would consider "terrible" fines on the magnet. Maybe 2-3x of yours, but one of them was claiming 80k miles, so not bad considering.

Best to put in an ATF like all-PAO Amsoil Signature Series Fuel Efficient, or similar Redline D6, or Mobil 1 Dexron HP, since they have the best base oil chemistry to resist oxidation for more miles. Use of other ATF brands is fine, just change every 75,000 miles or so if using others. I think Amsoil/Redlne/DexronHP can hit 150k or 200k if you get the initial early break-in metal fragments out first.
(A lot of ATF brands just buy "industry standard" Dexron VI additive chemicals from Lubrizol or Afton, etc., and then use Base Oil Interchange Rules to put in whatever level of longevity they are aiming for by using better base oils (PAO & POE, maybe GTL Group3+(?)) or cheaper base oils for the less expensive ATF oil on the shelves.)

And you are right about the majority of the wear being in the first "few" miles... one of the reasons the first oil change for a new car should be at 200-500 miles.

I ran across an Eaton co. patent the other day ( https://patents.google.com/patent/DE60130835T2/en ) which said the Ra (RMS peaks/valleys asperities roughness) should be between about 3 microinches to 10, ideally. From the looks of my Leaf magnets above, taken out at only 1,700 miles from new, Nissan must just let the gear teeth polish themselves in normal usage down from, guessing, 30 microinches surface polish at the factory. Hopefully ending up at 3-to-10 microinches Ra from normal use! ... Don't know any exact factory original Ra target value here. ...... All similar to ICE engine wear surfaces, so, yes, change the break-in oil or ATF fluid early, then not so much from then on is fine.

_________________________________________________________________________

Maybe another thread topic for later:
I discussed above how the Bolt's reduction gear lubrication & cooling design is way more complex than on many other EV's.
Funny how the Bolt is much more complicated than the Leaf in it's cooling system loops too.
The Bolt has 3 cooling circuits while the Leaf has only 1 (to cool the motor & electronics only) ..... Page 239 of:
https://my.chevrolet.com/content/dam/gm ... manual.pdf
I actually prefer the passively cooled Leaf batteries, using no liquid coolant, feasible since the Leaf uses unique battery design that should handle some extra temperature fluctuations better than some other battery designs seen on the road today. With 500,000 Leafs made so far, and only some early ones having trouble with too much heat, and/or with other work-arounds, Nissan engineers seem to know they can keep the design simpler. ....

Lately I've been comparing EV's. The Leaf (and Teslas) have been out so long that you'd think every new EV to come along would try to copy the relative simplicity to control costs & reliability better.