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AWD front motor whirring noise - now with Audio/Video - how many experience this?

72K views 690 replies 72 participants last post by  Phil Hyde 
#1 · (Edited)
OK, first. Loving the EV6 AWD.
We're learning a lot and so far, we've been able to either resolve or control the nuisances.
For example, rattle on the dashboard turned out to be the overhead shades which we "fixed" by stuffing in a piece of folded paper (quick easy fix).

Now for the query:
Has anyone else noticed a whirring sound when running the car in Eco or Normal with Regen not on Max?
I'm pretty sure this is related to the 2nd motor (Please chime in 2wd EV6ers if you also experience this!)

EV6-WhirringNoise-Video

Here's something we've learned:
When Regen is not on Max and the car is in Eco or Normal mode then there is a mild whirring (grinding) sound that oscillates with acceleration and deceleration.
It is most noticeable in the 28 - 40 mph range.
It is an annoying murmur/humming/whirring sound.
However, put the car into Full Regen, Winter, or Sport mode and the noise disappears instantly, regardless of Regen settings.

So, the good news is, we know how to "turn off" the noise, just not sure if the noise is deliberate or not.
Because we know how to control it this is now not even annoying, but until we figured out the cause it was a nuisance.

Note: "Engine theme" sound effects were off the whole time during our analysis/diagnosis

Thanks for responses in advance!
 
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#7 ·
Definitely sounds like it's happening when the front motor is idle, I've seen others post that i-pedal keeps the front motor engaged. I would guess that what you're hearing is the front differential. If you look at diagrams of the front motor/clutch, the clutch is on one half-sfaft. So if the clutch is disengaged, the front motor stopped, but the car moving, the "free" side will spin in the opposite direction of the side that is still coupled. That would cause the pinion gears within the differential to spin at an unusually high speed (they would normally not spin at all if both wheels were spinning at the same speed, same direction).
 
#8 ·
In eco it runs just one [motor in RWD mode].
This is only partially true. There is a power display for the center instrument cluster which shows you which motors are engaged and a rough idea of the power split between them. I don't use it very often, since I find it to be the least useful of the display modes for most driving. But I have learned the following:

The car is only more likely to operate in RWD mode in Eco than it is in Normal. In both Eco and Normal, the car will engage the front motor at low speeds, and disengage it at higher speeds. It also operates in AWD mode when regen is set to iPedal mode, regardless of the drive mode. But the control law is definitely not as simple as "Eco mode implies RWD mode".

<edit>
See also Drivetrain on EV's questions regarding the clutch
 
#13 ·
By the way, in case anyone is really curious, there is a cutaway of an actual front motor in this video. If you freeze it at 5:10, you can briefly see the differential, and one of the side gears within (circled in red in my screen cap below). Circled in blue is the pin of one of the pinion gears. These gears are small, and appear to be fairly coarsely pitched. I'd put money on this being the source of what you're hearing.
Automotive tire Automotive design Font Rim Material property
 
#28 ·
This is why I tend to avoid using i-Pedal or one-pedal driving on a regular basis, for the most part; I mean really, IMHO the only significant benefit from using it is it saves wear and tear on brake components vs. when using lower modes of regen.

In the same breath--hypothetically speaking wouldn't it be better to use your brakes (in combination with using non-one pedal regen) to slow the vehicle vs. having to rely (solely) on i-Pedal to slow down/come to a complete stop, in that using the motor to slow you down might result in increased wear on the motor vs. wear from using the brakes? IOW--it's cheaper to replace worn brakes than to replace a worn electric motor; same principle applies in the ICE world where some folks argue that it's better to use the transmission to slow you down vs. using brakes--again, it's cheaper to replace brakes than it is to replace a transmission due to premature wear.
 
#29 ·
IMHO the only significant benefit from using it is it saves wear and tear on brake components vs. when using lower modes of regen.
Even that isn't necessarily the case. When you apply the brakes, it uses regen to slow the car, and only blends in the friction brakes as needed (like if you stomp on it hard enough to indicate you want more deceleration than regen alone can provide). If you're hitting the brakes hard enough for it to apply the friction brakes, then you likely would have hit the brakes anyway even in ipedal mode. The exception is regen level 0... apparently it truly does disable regen in that mode, and hitting the brakes is pure friction brakes.

In i-pedal, to maximize efficiency you need to be mindful of the balance point on the accelerator between regen & acceleration, to coast whenever it's advantageous.
In other modes (except 0), you need to be mindful of the balance point on the brake pedal between regen and friction brakes, to avoid friction brakes to the extent possible.
 
#30 ·
Has anyone notice the bearing like sound coming from the front motor, while its either dormant or when its in eco mode? It almost sound like something need a little grease. When the motor is not engaged you can hear this rotating sound, but once you either turn on Sport mode or it receive power the noise will stop. At first I thought it was a frequency sound from how much power is being applied to the motors, but its for sure coming from the front motor while its idle and rotating.
 
#31 ·
 
#38 ·
Straight cut gears do whine, but the ones in the picture are not straight cut. Hopefully my AWD EV6 doesn't sound like that when it comes.

I have a Yamaha R1 with a BSB engine and Nova Transmission gearbox and it whines like a bastard. 😂 But on a race tuned bike its part of the deal. On an EV i wouldn't want it.

You will hear my gearbox whining at about 2:30 😂.
A run from Ramsey to Douglas at IOM TT road early one morning in 2011. Running the engine in at 180mph on the Mountain Mile.
 
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#40 ·
Yup very noticeable in myriad ev6 gt-line awd 2022 . It is very noticeable at 30mph in eco or normal mode. Sounds like you said a bad bearing or un greased. Kind of like a baseball card in your spokes of a bicycle or a leaf stuck somewhere. Definitely has begun to annoy me and am glad someone else hears it too. Is it supposed to sound that way or is this a concern?
 
#42 ·
I'm just on the verge of buying one and this post scares the bejesus out of me! There is a whole long string related to the Niro EV where they had a similar issue. See the post below. Consumer Reports reported the reliability of the Niro EV as quite good overall though.

 
#46 ·

Unfortunately the Niro EV had the same problem. They needed to replace the traction motor to fix the problem (see link above). I was just about to buy one. Not so sure now?
 
#47 ·
Unfortunately the Niro EV had the same problem. They needed to replace the traction motor to fix the problem (see link above). I was just about to buy one. Not so sure now?
I don't know if this makes you feel any better, but there's no indication that this is the same problem. We don't even know it IS a problem. All reports of this issue indicate that it only occurs when the front motor clutch is disengaged. The e-Niro doesn't even have a clutch. As I posted before, I would put money on this being gear whine from the differential. I would have rather seen a clutch on both half-shafts, but we don't KNOW that the differential can't handle that duty. Noisy? Apparently. But not necessarily a reliability issue.
 
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