lorenfb
Posts: 2510
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: Reduction Gear Oil Change - Benefits for Range

Thu May 13, 2021 7:31 pm

voltamps wrote:
Thu May 13, 2021 11:02 am
lorenfb wrote:
Thu May 13, 2021 10:14 am
Which makes this thread laughable!
My approximations don't quite cut it, that's true. That part is laughable. There is nothing like simply trying it on the road like what knightmb & estomax are doing.

The engineering paper that showed about a 1% loss from using thicker oil kind of nails the issue, done in a real transmission. The challenge for physics modelers is to include & know about enough things to simulate it right.

.......knightmb had a good point about there being some (small??) cascading savings effect, when your battery has to provide less watts flowing out to overcome all the losses in the Road Load. Anything saved is less you have to cool with pumps and fans.
My implication was not about your approximation, but that so much effort in this thread has attempted to reduce energy losses
in the transfer case by changing oils. Your analysis was more than adequate. Most with basic engineering backgrounds would
intuitively know little would be gained.
#1 Leaf SL MY 9/13: 76K miles, 47 Ahrs, 5.0 miles/kWh (average), Hx=70, SOH=73, L2 - 100% > 1000, temp < 95F, (DOD) > 20 Ahrs
#2 Leaf SL MY 12/18: 10.3K miles, SOH 109Ahrs/115Ahrs, 5.2 miles/kWh (average), DOD > 20%, temp < 105F

lorenfb
Posts: 2510
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: Reduction Gear Oil Change - Benefits for Range

Thu May 13, 2021 7:48 pm

voltamps wrote:
Thu May 13, 2021 10:55 am
knightmb wrote:
Thu May 13, 2021 9:15 am
Is there any additional energy saving when cooling the gear oil is mixed in?
Cooling the gears would make the oil stay thicker (more viscosity), and thicker oil loses even more energy. I say don't cool the oil too much since you actually want it to get as thin as possible, within limits.
knightmb wrote:
Thu May 13, 2021 9:15 am
....the fans kick on. All of that uses energy, not sure how much, haven't measured.
Fans are wasting energy. Those fans are getting rid of the heat during charging. It's not much lost energy. Certainly losses though. Gone.

On that same note, I was once curious as to how much heat losses you get charging & discharging an Li-Ion battery. I think I found you only lose around 2% lost to waste heat, depending on the amps going in or out, but usually not much.
knightmb wrote:
Thu May 13, 2021 9:15 am
..... avalanche effect within another system of the Leaf (cooling system) that uses a lot more power....
That's true to some extent. Think about it from the viewpoint of how much power (watts) has to flow on the wires feeding the motor. If the gearbox is more efficient, less watts are needed on those wires, less waste heat is generated. A small amount less. Same goes for better lower resistance tires, it results in the need for less watts on those wires & less heat too.

In fact, maybe the best way to look at all this is to use some hard facts we have. The Road Load, which has been measured on Leafs many times. Road Load includes the gearbox internal frictional drag, and all the dissipative energy losses up into the motor's internal windage losses.

Therefore, Road Load is great to tell us how many Watts must flow out of the battery itself !!!

Road Load at 60 MPH is 489 Newtons.
So that is 26.8 meters/second x 489 N = 13.1 kW power being drawn out of the battery at 60 mph.
Road Load from a 2013 Leaf (similar in a 2020 Leaf) from https://inldigitallibrary.inl.gov/sites ... 737951.pdf page 5.

Routing 13.1 kW power through the gearbox, 1% of that would be 0.131 kW savings using low visc oil. Like burning a 100 watt light bulb waste at 60 mph.
Read here with regard to Li-ion battery losses; viewtopic.php?f=34&t=27600&p=585497&hil ... ce#p585497

Which then leads to why TMS is a necessity for high charge rates, e.g. Tesla.
#1 Leaf SL MY 9/13: 76K miles, 47 Ahrs, 5.0 miles/kWh (average), Hx=70, SOH=73, L2 - 100% > 1000, temp < 95F, (DOD) > 20 Ahrs
#2 Leaf SL MY 12/18: 10.3K miles, SOH 109Ahrs/115Ahrs, 5.2 miles/kWh (average), DOD > 20%, temp < 105F

knightmb
Posts: 945
Joined: Mon Jan 12, 2015 7:41 pm
Delivery Date: 26 Feb 2021
Leaf Number: 306291
Location: Franklin, TN

Re: Reduction Gear Oil Change - Benefits for Range

Thu May 13, 2021 8:34 pm

lorenfb wrote:
Thu May 13, 2021 7:31 pm
My implication was not about your approximation, but that so much effort in this thread has attempted to reduce energy losses
in the transfer case by changing oils. Your analysis was more than adequate. Most with basic engineering backgrounds would
intuitively know little would be gained.
I think a lot of us, including myself know that the ULV alone won't gain much. I'm trying to figure out if the cascade effects are producing real gains for range, but I have limited data to work with, mainly my own data. That is why I'm excited to try this on an older Gen 1 Leaf with some definite before and after measurements. If the other Leaf is seeing some benefit that translates to real world gains, then it's a very cheap way to get more mileage that is permanent rather than temporary or expensive.
2020 Leaf SL Plus - (Manufacture Date March 2020)
2013 Leaf SV (8 faithful years of service before trade in at 75,679 miles)

knightmb
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Joined: Mon Jan 12, 2015 7:41 pm
Delivery Date: 26 Feb 2021
Leaf Number: 306291
Location: Franklin, TN

Re: Reduction Gear Oil Change - Benefits for Range

Thu May 13, 2021 8:42 pm

This is what steered me towards the idea after I found out the cooling fans kick on when the motor is under a high load during one of my 0 to 100 mph test. You'll have to fast forward to the 6:05 mark, that's when the fans blew the camera off it's mount while inside, during the 100 mph test. Also, the video makes the Leaf sound deafeningly loud inside. :lol: I only wanted the audio and a watchful eye on the fans, so I wasn't much into editing the video. Too bad the Leaf isn't that loud on the outside, that would certainly let everyone know you are approaching....
https://www.youtube.com/watch?v=kRKKYJCWoko
2020 Leaf SL Plus - (Manufacture Date March 2020)
2013 Leaf SV (8 faithful years of service before trade in at 75,679 miles)

estomax
Posts: 312
Joined: Fri Jan 20, 2017 9:23 pm
Delivery Date: 21 Jan 2017
Leaf Number: 424033
Location: Seattle

Re: Reduction Gear Oil Change - Benefits for Range

Fri May 14, 2021 11:48 am

knight is your range increase still holding up? My average has stuck at 3.9 miles per kwh over the 3.5 that i had earlier, so up in theory over the last 1000 miles or so, but hard to say how much of it is from the warmer weather or not. Heavy foot is still in use and freeways are not too clogged so speeds are higher than pre pandemic. Gut feel wise my average may be 0.1-0.2 miles per kwh more than before at these speeds, a small delta if anything, but still fun to experiment.
2013 Leaf SL
27k, 93% SoH 2/17 46k, 94% SoH 2/18
62k, 87% SoH 2/19 75k, 83% SoH 2/20
81k, 81% SoH 2/21

knightmb
Posts: 945
Joined: Mon Jan 12, 2015 7:41 pm
Delivery Date: 26 Feb 2021
Leaf Number: 306291
Location: Franklin, TN

Re: Reduction Gear Oil Change - Benefits for Range

Fri May 14, 2021 12:27 pm

estomax wrote:
Fri May 14, 2021 11:48 am
knight is your range increase still holding up? .....
Sure is, a pile of data I have so far now, for one of the longer trips that has no stop lights, signs, etc.
I put the dates to it this time, easier to work with data now...
70 mph test
4/1/2021 -- 25.1 miles 3.6 miles/kWh
4/3/2021 -- 25.1 miles 3.6 miles/kWh
4/4/2021 -- 25.1 miles 3.6 miles/kWh
4/6/2021 -- 25.1 miles 3.6 miles/kWh
4/15/2021 -- 25.1 miles 3.9 miles/kWh <- Gear Oil Change *after*
4/23/2021 -- 25.1 miles 3.9 miles/kWh
4/24/2021 -- 25.1 miles 4.0 miles/kWh (windy day, probably tail wind bonus)
4/25/2021 -- 25.1 miles 3.9 miles/kWh
4/27/2021 -- 25.1 miles 3.9 miles/kWh
5/7/2021 -- 25.1 miles 3.9 miles/kWh
5/8/2021 -- 25.1 miles 3.9 miles/kWh

For the higher speed drive, seems to be about 0.2 - 0.3 increase.

For the lower speed routes, the first increase I saw was about 0.4 increase, the warmer weather has skewed it up to 0.6 increase. I keep my tire pressure as close to 42 PSI as I can, but the hotter weather means the tires can reach +46 PSI on sunny days, so it seems to have no affect on the high speed driving (which makes sense, air friction), but a bump up on the lower speed, stop and go, driving. Probably rolling resistance related at lower speeds.

It is fun to charge the vehicle to 100% and have unrealistically high GOM range estimates of +272 miles :lol:
2020 Leaf SL Plus - (Manufacture Date March 2020)
2013 Leaf SV (8 faithful years of service before trade in at 75,679 miles)

knightmb
Posts: 945
Joined: Mon Jan 12, 2015 7:41 pm
Delivery Date: 26 Feb 2021
Leaf Number: 306291
Location: Franklin, TN

Re: Reduction Gear Oil Change - Benefits for Range

Fri May 14, 2021 1:02 pm

This is what the Nissan EV Connect website showed after the gear oil change. :shock:

Gear Oil Change on 9th of April
Image
2020 Leaf SL Plus - (Manufacture Date March 2020)
2013 Leaf SV (8 faithful years of service before trade in at 75,679 miles)

voltamps
Posts: 128
Joined: Thu Dec 17, 2020 6:13 pm
Delivery Date: 14 Dec 2020

Re: Reduction Gear Oil Change - Benefits for Range

Fri May 14, 2021 1:36 pm

Wow, many people reporting gains after a gear fluid change. Maybe it's the 120 ppm or so (Blackstone analysis) metal particles floating around in the old stuff, getting on the roller & ball bearings, etc., that puts up some more resistance? Those magnets don't get it all out, we know. People who put in the thicker Redline D6 have even reported some gains, wrong or right, who knows?

Ford may not want to come out and say publicly why they put in thin ULV fluid in their new Mach E, & how much Range went up due to that. People tend to criticize them for sacrificing longevity for efficiency, as what happened back when they switched about everything to 0w-20 oil.

GM's new Bolt EUV got an official EPA Range Rating of 247 miles recently, just shy of a marketing-win "250" mile round number. Since Range on the Monroney sells more new EVs, if I was at GM I would have told them to OE spec the Michelin Energy Saver A/S tires with 51 psi max sidewall pressure, and put on a new placard cold pressure on the door jam of 45 psi. I ran that 51 psi sidewall max pressure version (they make both a 44 psi & 51 psi versions in that line of tires for some strange reason) on my old '16 Focus EV, so they do exist.

-- Then of course tell them to put Dexron ULV (like Mercon ULV & Valvoline ULV thin). With both tires & the thinner fluid, they could've gotten to the psychological marketing threshold of an even 250 !
2020 Leaf SV
2016 Ford Focus Electric (traded in at 34k miles, 5 years)

knightmb
Posts: 945
Joined: Mon Jan 12, 2015 7:41 pm
Delivery Date: 26 Feb 2021
Leaf Number: 306291
Location: Franklin, TN

Re: Reduction Gear Oil Change - Benefits for Range

Fri May 14, 2021 3:32 pm

voltamps wrote:
Fri May 14, 2021 1:36 pm
Ford may not want to come out and say publicly why they put in thin ULV fluid in their new Mach E, & how much Range went up due to that. People tend to criticize them for sacrificing longevity for efficiency, as what happened back when they switched about everything to 0w-20 oil.
Is the new Mustang Mach E range (top end model with largest battery?) now greater than the same year Mustang gas model range? I remember that being toted around a lot on social media during the artificial "gas" shortage here in TN this week. A lot of people in my town seem to own the Mach E for some reason.
2020 Leaf SL Plus - (Manufacture Date March 2020)
2013 Leaf SV (8 faithful years of service before trade in at 75,679 miles)

knightmb
Posts: 945
Joined: Mon Jan 12, 2015 7:41 pm
Delivery Date: 26 Feb 2021
Leaf Number: 306291
Location: Franklin, TN

Re: Reduction Gear Oil Change - Benefits for Range

Fri May 14, 2021 3:47 pm

It didn't take me much research to find the answer! :lol: I'm assuming the Mach E would get better range at non-highway speeds, so around town driving should go quite far.

Ford Mustang Mach E (2021)
Standard - 230 Miles of Range
Max Battery Size - 305 Miles of Range

Ford Mustang (2021) - Tank Size 16 gallons
Smallest Engine Coupe 21/30 MPG (city/highway) - EcoBoost
Range could be 336 / 480

2 Door Convertible 20 / 28 MPG - Range 320 / 448

GT - 15 / 24 MPG - Range 240 / 384

Mach 1 - 15 /23 MPG - Range 240 / 368
2020 Leaf SL Plus - (Manufacture Date March 2020)
2013 Leaf SV (8 faithful years of service before trade in at 75,679 miles)

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