[roryhw]

M60i owners please let me know if you're also noticing what I can best describe as a subtle drivetrain vibration followed by also subtle but chunky/rough/uneven braking when easily slowing down.

It happens consistently when slowing through 45 and 25mph. Before and after these speeds braking is completely normal. Braking moderately hard kind of hides the feeling and it's much more noticeable in normal gentle and easy driving conditions.

I have also found that if I change the gearbox to (N) neutral, the braking is perfectly smooth as expected. I suspect the above behavior has something to do with the mild hybrid system playing a role in braking but I can't be sure?

Have a look at this review by Throttle House comparing the X7 with the GLS and Range Rover - the guys talk about what seems to be the same thing on the X7 M60i as well.

I'm curious if others are experiencing this and if it's something that can be (or has been?) corrected through a software/firmware update or hardware replacement?

My M60i only just passed 4000 miles and this isn't a new behavior - it's been a characteristic of the day from day 1 but it just doesn't feel right - I've owned BMWs for 20+ years.

Appreciate any shared experiences or advice here. Thanks.

Watch this X7 review from 8:00 into the video: https://www.youtube.com/watch?v=vuUaXXNgZFI&t=470s

[chicagofan00]

I do not experience anything like that in my M60i.

[Chastizer]

Sorry to hear that you experience vibrations. I do not experience anything like that in my M60i either.

[parky1215]

Braking in normal day to day driving situation is smooth as butter in my M60i.

[RichardMille1015]

I have noticed this on my 24 X7 M60i. I have about 2k miles on it now and I noticed it almost immediately after picking it up. The vibration is definitely subtle with slight differences depending on the rate of slow down. The brake pedal feels a little weird too during that time. I will say as a passenger you don’t notice it much at all. I am surprised by it though. Surely has something to do with the mild hybrid/regen.

[roryhw]

Originally Posted by RichardMille1015

I have noticed this on my 24 X7 M60i. I have about 2k miles on it now and I noticed it almost immediately after picking it up. The vibration is definitely subtle with slight differences depending on the rate of slow down. The brake pedal feels a little weird too during that time. I will say as a passenger you don’t notice it much at all. I am surprised by it though. Surely has something to do with the mild hybrid/regen.

I also think it’s mild hybrid related. Did you try switching to neutral to see how it feels during braking without transmission engaged?

I have decided to get the dealership to look at it. Booked for early April. I’ll share an update after.

[RichardMille1015]

Yes, I have tried braking in neutral. It is smooth as I would expect. The vibration seems to happen when the car is slowing and downshifting as necessary (as late as possible for fuel economy) between 45-25.

Additionally, when im in sport mode/using the paddles I don’t feel the vibration issue (brakes can still feel weird). I assume this is because the car/me is downshifting earlier so the car stays higher in the revs.

From what I’ve experienced so far I think it has to do the mild hybrid motor “assisting” with the minor downshifts. When normally slowing, instead of injecting a little extra fuel into the engine to downshift from say 4 to 3 gear (1000 to 1250ish RPM), the car uses torque from the electric motor to spin up the engine to the desired RPM for the downshift.

When slowing the 6-5-4-3-2 gear changes occur pretty quickly one after another. This is constantly sending spurts of torque to the engine without the engine being under load as it would be in a car without mild hybrid. This is what I’m pretty sure is causing the drivetrain vibration at those speeds.

I could be wrong but after analyzing this issue for a while I can’t come up with anything else. I will also try to get my car to the dealer to see if they know anything about it. Will keep updated.

[cmargosi]

I wouldn't call it a vibration, but I certainly feel my 24 M60 brakes differently than a non hybrid car. I haven't tried the neutral trick, but the brakes feel a bit off. I find it happens at slower speeds.

I also notice if I drive in Eco mode I get a lot of engine braking in certain circumstances.

It doesn't really bother me...but it feels different for sure.

[roryhw]

Update following a dealer visit:

The dealership service foreman inspected my vehicle with the BMW area engineer who was at the dealership.

Following a test drive the area engineer did not find any abnormality in the braking operation.

The sensation during braking operation is apparently a characteristic of the mild hybrid drivetrain and the feeling I reported does not constitute a defect. No repairs or corrective measures are required.

So… it’s good to know there is no defect and I guess I just have to get used to the different feeling of the M60i mild hybrid helping braking while slowing at low speeds.

[MikeX521]

I have the same going on in my ‘24 50e.
I also had the dealer look at it when I took it in and it came back as normal and it’s the regenerative breaking doing its ‘thing’.
I assumed as much, but I am surprised that there is that mild shutter regardless… must be some type of harmonic interaction at that speed causing it. Other than that small speed range affecting it, it’s smooth as butter at all other speeds.

[roryhw]

Originally Posted by MikeX521

I have the same going on in my ‘24 50e.
I also had the dealer look at it when I took it in and it came back as normal and it’s the regenerative breaking doing its ‘thing’.
I assumed as much, but I am surprised that there is that mild shutter regardless… must be some type of harmonic interaction at that speed causing it. Other than that small speed range affecting it, it’s smooth as butter at all other speeds.

Thanks for sharing and it’s actually reassuring to hear it’s happening with the 50e too.

So far we know X7 M60i, X5 M60i and X5 50e are all doing this.

Still don’t love it but slowing getting used to it.