[Go FasTA]

On Monday I started noticing a slight vibration in the steering wheel of my M40i during my morning commute. As I continued to monitor the situation over the last couple of days, I believe it may be drivetrain related. It seems most pronounced between 50-55 MPH and even more so when under light load (such as maintaining speed up a slight incline). It's possible it could be a tire/wheel assembly out of balance, but it behaves more like an issue with the drivetrain itself. I notice some slight audible rumbling when it's most pronounced, but it's hard to know if that's always been there under those conditions. I've tested in sport and comfort modes and the vibration is still there under the same conditions in sport even though the transmission is in a different gear. This makes me think that the problem is post-transmission. I've scheduled a service appointment for Tuesday and will update this thread with the findings. For reference, I currently have 3400 miles and took delivery in April.

[arciga18]

Good luck. Sounds like a headache to diagnose /replicate and remedy .

I vote steering rack/ pinion.

See early f30 issues on the forums .

[bmwx3guy]

I don’t have a M40 but 2018 X3. I have the same issue and it’s at the dealership now to find out what’s going on.

[Go FasTA]

Originally Posted by bmwx3guy

I don’t have a M40 but 2018 X3. I have the same issue and it’s at the dealership now to find out what’s going on.

I don't know if this makes me feel better or worse

[bmwx3guy]

Well just take it to the dealer and see what they say.

[Go FasTA]

Originally Posted by bmwx3guy

Well just take it to the dealer and see what they say.

I am. They didn't have an opening until the 26th, so it'll go in then.

[mjdth]

I'm a little over 2,000 miles. In the last week or so I've noticed a metallic vibration sound (but can't feel anything in the steering wheel) when the car shifts gears when accelerating between 15-35mph. Really just reminds me of how old beater trucks would sound when you're accelerating, metal noises. Only happens when I'm accelerating at a relatively regular rate (probably around 2-4k rpm). Can't remember if the car always sounded like that, not sure if this is related of if I'll bring it in.

[HornMfan]

Originally Posted by mjdth

I'm a little over 2,000 miles. In the last week or so I've noticed a metallic vibration sound (but can't feel anything in the steering wheel) when the car shifts gears when accelerating between 15-35mph. Really just reminds me of how old beater trucks would sound when you're accelerating, metal noises. Only happens when I'm accelerating at a relatively regular rate (probably around 2-4k rpm). Can't remember if the car always sounded like that, not sure if this is related of if I'll bring it in.

I've noticed the same issue with the "pinging" sound on acceleration, especially moderate acceleration. Has anyone else noticed a bounciness or rocking at stops or squishy feeling brakes? I seem to have that issue, as well as a rattle from the passenger rear side. Could be the tonneau cover, but need to take that off and test to be sure. One other thing...under hard acceleration does anyone feel a "pulling back" feeling almost related to the exhaust if in sport mode, manually shifting?? Doesn't always happen but have felt it more lately...like rough shifting, but almost feels like it's exhaust related...which reminds me, a few times I've put it in Sport mode and not been able to hear the crackles (like revving it up to 4K or so in 1st and then letting off,etc). It seems to work if I hit comfort and then go back into sport. Maybe an issue with the valves in the exhaust. I guess I have enough annoyances now to bring it in.

[arciga18]

Originally Posted by HornMfan

I've noticed the same issue with the "pinging" sound on acceleration, especially moderate acceleration. Has anyone else noticed a bounciness or rocking at stops or squishy feeling brakes? I seem to have that issue, as well as a rattle from the passenger rear side. Could be the tonneau cover, but need to take that off and test to be sure. One other thing...under hard acceleration does anyone feel a "pulling back" feeling almost related to the exhaust if in sport mode, manually shifting?? Doesn't always happen but have felt it more lately...like rough shifting, but almost feels like it's exhaust related...which reminds me, a few times I've put it in Sport mode and not been able to hear the crackles (like revving it up to 4K or so in 1st and then letting off,etc). It seems to work if I hit comfort and then go back into sport. Maybe an issue with the valves in the exhaust. I guess I have enough annoyances now to bring it in.

My exhaust was just replaced due to a rattle in the rear passenger area. I'll have more details tomorrow if they let me pick up the X3

[HornMfan]

Originally Posted by arciga18

My exhaust was just replaced due to a rattle in the rear passenger area. I'll have more details tomorrow if they let me pick up the X3

Yes please let me know. I'm going to take the tonneau cover off and store it in the space under the rear cargo mat and see if it still happens. If it does, it's gotta be the exhaust I would think.

[mjdth]

Originally Posted by arciga18

My exhaust was just replaced due to a rattle in the rear passenger area. I'll have more details tomorrow if they let me pick up the X3

Yes we've been trying to pinpoint a rattle. Sounds like it's coming from rear passenger side until you sit in the back seat, then you can't tell where it's coming from. Happens at lower speeds and is more pronounced over bumps. Seems to be a separate issue from the strange engine noise during acceleration. This one also has been driving me a little crazy...

[BMWZ4]

Wheel bearing(s)?

[BobsM3Coupe]

Originally Posted by arciga18

My exhaust was just replaced due to a rattle in the rear passenger area. I'll have more details tomorrow if they let me pick up the X3

I don't hear a rattle in the rear passenger area, but for the last couple of cold starts, for the first 10 seconds or so, it sounds like something is loose in the exhaust system. Then even though the exhaust is still loud, the rattling sound disappears. Warm starts doesn't do it. I'll be keeping my ears open.
For the heck of it just now, I tapped firmly on the muffler with a rubber mallet and it sounds like something is loose inside the muffler. Maybe a baffle broke loose?
Can someone try the rubber mallet test on their M40i when the car has sat overnight? TIA

[J-sun]

Originally Posted by arciga18

My exhaust was just replaced due to a rattle in the rear passenger area. I'll have more details tomorrow if they let me pick up the X3

Originally Posted by arciga18

My exhaust was just replaced due to a rattle in the rear passenger area. I'll have more details tomorrow if they let me pick up the X3

I'm experiencing the exact same thing - a clattering rattle beneath the rear passenger floorboard - especially noticeable during gentle acceleration between 1500-2500 RPM. This and the rattle in the driver's side B pillar are annoying the {bleep} out of me.

I'm interested in what your service rep has to say about it.

[mjdth]

Originally Posted by arciga18

My exhaust was just replaced due to a rattle in the rear passenger area. I'll have more details tomorrow if they let me pick up the X3

Any update on this?

[arciga18]

Originally Posted by mjdth

Any update on this?

Don't want to derail the thread but here is the paperwork.

Rear rattle appears to be gone. Did a lot of stop and go driving yesterday after pick up. The story is that one of the welds was broken on the exhaust.

I did notice that the engine itself is loud at idle. I kinda new this but noticed it more after my SA walked me around the car looking for issues.

[mjdth]

Originally Posted by arciga18

Don't want to derail the thread but here is the paperwork.

Rear rattle appears to be gone. Did a lot of stop and go driving yesterday after pick up. The story is that one of the welds was broken on the exhaust.

I did notice that the engine itself is loud at idle. I kinda new this but noticed it more after my SA walked me around the car looking for issues.

Thanks. Bringing mine in tomorrow for this, hopefully they'll be able to get it fixed.

[kamek]

Originally Posted by BobsM3Coupe

I don't hear a rattle in the rear passenger area, but for the last couple of cold starts, for the first 10 seconds or so, it sounds like something is loose in the exhaust system. Then even though the exhaust is still loud, the rattling sound disappears. Warm starts doesn't do it. I'll be keeping my ears open.
For the heck of it just now, I tapped firmly on the muffler with a rubber mallet and it sounds like something is loose inside the muffler. Maybe a baffle broke loose?
Can someone try the rubber mallet test on their M40i when the car has sat overnight? TIA

I have the same little rattle at start up. Inclined to think it's normal but please update us if it actually isn't!

[BobsM3Coupe]

Originally Posted by kamek

I have the same little rattle at start up. Inclined to think it's normal but please update us if it actually isn't!

It's probably normal for the M40i. But I will keep the forum updated if I find otherwise.

[mjdth]

Got a call from the dealer picking the car up today. They replaced my blower motor and said they fixed the rattle from the right rear sunroof area. Regarding the tinny vibrations coming from the exhaust, he said they had to order a new muffler or exhaust, but it's backordered and won't be here for maybe a month or two. Hopefully nothing falls off in that time...

Fun part was the loaner I got for one day had no gas in it and was at the warning level. Had to stop to put in some gas before being able to drive home, thought I'd have it for more than one day.

[mjdth]

Nevermind. The annoying rattle in the rear-right of the car is 100% still there. Didn't hear it yesterday on the way home from the dealer. Today it was glaringly obvious at any speed under 30mph.

[arciga18]

Originally Posted by mjdth

Nevermind. The annoying rattle in the rear-right of the car is 100% still there. Didn't hear it yesterday on the way home from the dealer. Today it was glaringly obvious at any speed under 30mph.

Which Dealer. I'm local.