[Ron Jeffries]

over rough pavement, new snow tires, new MP exhaust. car has deep resonance from left front, sounds low down inside or below car. seems that the stereo can produce it sometimes as well. seems to be road speed dependent, not engine speed.

very strange and quite irritating.

[Dylan86]

Could it be the "Active Sound"? It's the phony engine sounds that come through the stereo..

[jmwilson125]

Originally Posted by Ron Jeffries

over rough pavement, new snow tires, new MP exhaust. car has deep resonance from left front, sounds low down inside or below car. seems that the stereo can produce it sometimes as well. seems to be road speed dependent, not engine speed.

very strange and quite irritating.

Maybe it's just the tires and it seems to be coming from that area? Any wheel change as well? Could it be rubbing?

[Ron Jeffries]

ASD is off, plus this is much louder than ASD.

It’s a single tone, doesn’t rise or fall with speed or engine revs. sometimes there, when car speed over slightly rough pavement is right. something’s picking up and amplifying tire/wheel vibration or the like ...

except it seems some notes from the radio will do it as well, but only sometimes. couldn’t get that to happen when stopped, so not certain on the radio thing.

[amw896]

I'm gonna say it's the snow tires. I have snow tires on my mazda3 and they ride and sound like absolute crap on anything other than snow.

[wdc330i]

Stop worrying about stuff and enjoy driving your new car? I'd also suggest stop modding it, until you settle into every day life with it. Let it rest for 6 months or so, then figure out if you need to change anything more.

[Rony316]

Remove all variables first and re-examine. Empty cup holders, center console, glovebox, trunk. Everything. Had a weird resonance that was caused by a can in the door cup holder. Drove me crazy.

[Ron Jeffries]

it’s not the snows: i can hear them, too, and their tone is higher, more of a ringing, and changes with road speed. the resonance does not. plus, with window open, i hear them, but not the resonance, outside.

agreed on eliminating things by emptying the car, and i’ll do that. there’s not much in it, since it’s new, but there is stuff.

it was not making the noise the first few days on the snows, nor first few days with MPE. Just started yesterday. It’s like a panel is loose, or possibly something underneath bumping, but it’s a low dull drumming kind of sound, not a sharp rattle.

As for just enjoy the car, sure, but this is loud enough and resonant enough that even with radio loud, you hear it. on a trip it’d drive you crazy.

natch, i’ll take it to dealer if emptying the car doesn’t fix it.

[Ron Jeffries]

Is the exhaust pipe from engine to rear on the left side of a left hand drive M240i? I just had the MPE put on before the noise started. I wonder if in hooking it up they may have allowed the exhaust to bump against the car somewhere along the way.

Guess not according to the pics I can find ... still, that's the most recent change before this weird drumming noise.

[Maynard]

Looks like you are thinking to bring it to the dealership, which would be my suggestion. Might be worth considering an alignment check, as that can give you a sort of low grinding noise (at least that was what tipped me off that I was out of spec). Also might try pulling the stereo fuse to see if that stops it, as a way to r/o the ASD and related stereo acoustics.

[Ron Jeffries]

Originally Posted by Maynard

Looks like you are thinking to bring it to the dealership, which would be my suggestion. Might be worth considering an alignment check, as that can give you a sort of low grinding noise (at least that was what tipped me off that I was out of spec). Also might try pulling the stereo fuse to see if that stops it, as a way to r/o the ASD and related stereo acoustics.

Yeah gonna take it in Thursday. I'm almost convinced it could just be tire noise but its deeper, more bumpy, and less ping than usual tires. When I started it this morning I def heard what sounded like exhaust rattle, during that rough period right after a cold start. Could have just been the vans but deeper in tone than I expect.

I figure they might find something, might blow me off. If it's the tires I wonder if a different brand of snows from the Contis might be quieter.

[Maynard]

The tire noise I get tends to be very surface-dependent, so it will on-off as you hit patches of different pavement and vary with speed. Mis-alignment would tend to be more steady like you describe, may vary with turning. I suspect that my car was poorly aligned from delivery, since the noise I questioned had been there all the time, but went away once they corrected alignment. That start-up rattle may be a common feature of the sport exhaust valve - you can search for a thread here that does into a lot of detail about what is normal vs. stuck valve (but wouldn't expect it to give a deep rumble, seems more like it makes a rattle).

[Ron Jeffries]

Originally Posted by Maynard

The tire noise I get tends to be very surface-dependent, so it will on-off as you hit patches of different pavement and vary with speed. Mis-alignment would tend to be more steady like you describe, may vary with turning. I suspect that my car was poorly aligned from delivery, since the noise I questioned had been there all the time, but went away once they corrected alignment. That start-up rattle may be a common feature of the sport exhaust valve - you can search for a thread here that does into a lot of detail about what is normal vs. stuck valve (but wouldn't expect it to give a deep rumble, seems more like it makes a rattle).

there is allegedly no valve on the 2018 m240i. i’ll try to remember to have them think about alignment. on a new car, what’s up with german precision these days?

[Ron Jeffries]

I'm starting to think that the noise might actually be mostly the tires. Are the Conti WinterContacts particularly loud? I'm sure I'm getting some resonance, sometimes, from a body panel or the exhaust but it could be the tires starting things. I may have to find some grass to drive on as a test ...

[Ron Jeffries]

Took car to dealer today and shop foreman drove it. He seems pretty sure all the noise is the ContiWinterContact tires. I'm not convinced but not willing to give them the car for a day to search for a sound he can't even hear.

[boostm3]

Originally Posted by Ron Jeffries

ASD is off, plus this is much louder than ASD.

.

What????? There's something louder than ASD?