[chris-c]

If it's HOT like it is now and I'm not running AC it's fine.
If it's HOT like it is now and I am running AC i can make the noise smashing it 1st --> 2nd, 2--> 3rd and sometimes 3rd --> 4th. The 1st to 2nd and 2nd to 3rd is almost guaranteed fo rthe first 5 minutes of driving.

[VVlasy]

Even after new belt and tension the squeak came back, seems like it wont ever get resolved.

[Mr. 340]

I have also had this issue for the past year and a half of ownership and the dealership said it's normal. Haven't even bothered in looking into it again, I'll fix it once something actually happens cause apperantly there is no fix for it so far.

[G80indy]

Wow
Considering a 440 vert, but it will be even more audible with the top down?
👎🏻

[arvi604]

I’m glad I found this thread. My 340i xDrive is doing it without fail. Cold start, sport + 3k+ upshift from 1st to 2nd. Unmistakeable squeak. I guess as long as it’s not tranny related I am not too worried but would like to eventually get it resolved. The video posted earlier in this thread is the exact sound I hear.

[Supr3me]

I had this issue when I first purchased the car, typically only when the AC or blower fan was active.
Weird thing is that after I started adding power, seems like it's gone away. Does anyone here who is flashed stage 2 or better have the issue?

[Astute]

Originally Posted by Supr3me

I had this issue when I first purchased the car, typically only when the AC or blower fan was active.
Weird thing is that after I started adding power, seems like it's gone away. Does anyone here who is flashed stage 2 or better have the issue?

I have the same issue with stage 2 BM3 and stage 3 xHP. Pretty annoying, but it typically only happens right after I start the car with the AC on from 1st to 2nd and from 2nd to 3rd.

[Sleeper340i]

Originally Posted by Supr3me

I had this issue when I first purchased the car, typically only when the AC or blower fan was active.
Weird thing is that after I started adding power, seems like it's gone away. Does anyone here who is flashed stage 2 or better have the issue?

Good catch Supreme. Now that I think about it the last time I heard it (or last time I noticed) was after I first got my car back from the shop after fresh Pure 800 install with it few weeks in the shop( no tune yet, stock turbo power that drive ) Was not warmed up fully and sport mode manual 1-2.

Mine usually made the sound occasionally but not too often( back then in sport/sport + and mainly manual mode 1-2 when not warmed up including when on stage 2. Thought my trans was crapping out, or that it was screaming to me that I needed a transmission fluid change.

Don't think I heard it much since going Pure 800 (tuned) or I could have got used to it and accepted it. Will report back again once I get my car back.

Anybody that has done a transmission fluid change have you noticed the sound still present?

[VVlasy]

Originally Posted by Sleeper340i

Good catch Supreme. Now that I think about it the last time I heard it (or last time I noticed) was after I first got my car back from the shop after fresh Pure 800 install with it few weeks in the shop( no tune yet, stock turbo power that drive ) Was not warmed up fully and sport mode manual 1-2.

Mine usually made the sound occasionally but not too often( back then in sport/sport + and mainly manual mode 1-2 when not warmed up including when on stage 2. Thought my trans was crapping out, or that it was screaming to me that I needed a transmission fluid change.

Don't think I heard it much since going Pure 800 (tuned) or I could have got used to it and accepted it. Will report back again once I get my car back.

Anybody that has done a transmission fluid change have you noticed the sound still present?

Its not transmission, I have had 2 trans oil changes. What made a difference for a about a year and a half was the belt change+belt tensioner I had done. But it eventually came back.

My subjective unexpert opinion is that this issue requires BMW to redesign either the belt, tensioner, pulleys or all of them.

About the relation of squeak noise getting lower on higher power. I have the opposite experience. The squeak got louder after adding MPPSK

[z3n0mal4]

Hey guys,

I'm also a 440i owner that shares the funky squeak. It has happened the past months on a more frequent note, so i came here to check it out and well it seems i'm not the only one.

What i did manage to observe on my car is that it happens when it's really hot outside, with a hot engine, not on cold starts. It only happens during 1st shift from 1 to 2, in sport mode (i always drive in sport mode), usually with the AC ON.
Now i wonder if it's not something to do with the timing of the car being stopped after a run (usually in town, 10-20mins drives). What i mean is i drive the car, then i leave it for an hour or so, air inside engine and turbo /etc stays hot, summer outside and everything hot inside engine bay, then i start the car, leave it for a minute or two like i usually do and floor it = squeak.

I'll talk to my local dealer when i go for the next service, next month probably, but i'm pretty confident they won't know shit.

[J3Vr6]

Originally Posted by Supr3me

I had this issue when I first purchased the car, typically only when the AC or blower fan was active.
Weird thing is that after I started adding power, seems like it's gone away. Does anyone here who is flashed stage 2 or better have the issue?

Stage 2 MHD OTS here and it still does it. When I had the JB4 before, it used to also do it.

[John.K]

Bump. Add me to the club. Has anybody got any further updates to share? BeaminBimmer , DG20 are you still having the noise also? Asking you two as i gathered yours were the most prominent reading this thread from the beginning; i.e. making the noise daily (mine is too)

On my car is it happens when it's really hot outside, with a hot engine. I almost want to say it does it only when the trans is clicked over to the left, to the sport shifting mode... And the throttle has to be on Sport or Sport+ I reckon. As i automatically click the toggle soon as i've pulled out of my parking spot.

[BeaminBimmer]

Originally Posted by John.K

Bump. Add me to the club. Has anybody got any further updates to share? BeaminBimmer , DG20 are you still having the noise also? Asking you two as i gathered yours were the most prominent reading this thread from the beginning; i.e. making the noise daily (mine is too)

On my car is it happens when it's really hot outside, with a hot engine. I almost want to say it does it only when the trans is clicked over to the left, to the sport shifting mode... And the throttle has to be on Sport or Sport+ I reckon. As i automatically click the toggle soon as i've pulled out of my parking spot.

I no longer have my 340. However my brother got one as soon as I got an x5 and it does it also. He's got a 2018. Mine was a 2016... after numerous dealer visits and an opened case with Germany apparently its normal! 🤷🏻*

Mine did it all the time at some point. Comfort/sport/sport+ hot or cold AC on or off. Once the engine was warm enough it didn't happen anymore.

[Handley05]

Figured I would drop this for anyone looking in future. My 2016 340 had this issue from the video, a squishy shoe on basketball court noise, which sounds like possible tires gripping on cold wet pavement. It only did it for me when cold at 48k miles when doing mid rpm shift with mid -heavy throttle. Some people claim its all temps and with or without ac. That is bc its belt and tensioner and all scenarios could be causing glazed belt to slip a pinch since there are next to no accessories running off the serp belt causing belt float with weak belts/tensioner. Had my tensioner and belt r/r under cpo. Couldnt reproduce the noise after.

[MaximusJ]

Same as supr3me; since i've switched from JB4 to BM3, the problem completely disappeared.

[Roach1]

I have a noise but it's not a squeak it's a screech that lasts a second when in sport mode and right after taking off from a stop . Any experiencing the same ?

[ibleedblue89]

Hey guys, I am the owner of a 2017 340i 8 speed AT. My car is currently at a little over 100k miles. I have had this issue since the car was new and I honestly always thought is was the sound of my tires slipping because of how aggressive the car shifts in sport+ mode. Either way, my car has never had any major mechanical issues and still pulls like a freight train to redline. No transmission or traction issues at all. I daily drive my baby and regularly launch the car hard, accelerate hard through multiple gears into xxx mph speeds [late night and on closed private roads ] , drive in SoCal "LA" traffic, put the engine under load while in manual mode [mostly forgetting to downshift on the highway], and occasionally enjoy some spirited backroad drives. Of all the noise quirks this car has, this chirp has bothered me the least, probably because the slight pop the car makes on upshifts is way more fun to focus on.

Main point, besides being mildly annoying, this noise doesn't seem to anything to lose sleep over. My car also thuds from the gas tank when low on gas, and occasionally the muffler buzzes on start up. I'll take these "issues" over all the sh** I had to deal with while owning my 2 e9x N54 335i(s).

[BMWILUVU]

I had short squeaks whenever the AC went on but it has since gone away mysteriously after a dealership visit a year ago. Try to see if you still get the squeak with the AC off.

[VVlasy]

The squeak now for me has gotten to the point that when summer starts, it happens in any gear, even 6-7-8. Some of you say you don't notice any adverse effect. But I can definitely feel a short lack/delay of power while the belt is slipping. Maybe a higher load caused by drag of the AC compressor.

Replacing the belt, tensioner, alternator pulley and maybe AC compressor pulley. I will report back with any findings.

100K KMs, but squeak was there since about 30K I would say

Edit 1: Replacing the drive belt improved the squeak significantly. Now it only happens 1-2 in sport+. Will continue investigating, have a wobble in water pump pulley, will be next to be replaced.

[jlefkowitz99]

did anyone ever fix this issue? I have a 330i g20 and I hear the EXACT same noise when shifting with ac. Goes away after a few mins. it just started randomly at 54k miles. It is honestly driving me crazy. please tell me there is a fix?