Weird Sound Coming from Engine

[Jhenka]

Hey guys I have some sort of weird low pitched whine coming from my car at around 60-65 mph at 1800-2200 rpms. Cant figure out what it is and if its normal or if should i go get the car checked out at the dealers. Was wondering if any of you guys had the same issue? Any help would be greatly appreciated.

The whine comes on when driving the car cold at around 60 mph and stays there as the car gets warmed up. The only difference is it gets louder as i go higher into the rpms but gets drowned out by the exhaust. This is my first winter with the car and i only started noticing the noise as it go colder (Below 30F). I also had the JB + BCM installed about a month ago but i've been running map zero the whole time.

In the two videos below I'm cruising at 60-65 mph getting it up to 2200 rpms then letting go of the gas/slightly nudging it to accentuate the noice. The exhaust quiets down but the whine stays till the car gets below 1800 rpms.

[13M5F10]

Sounds like the rear differential to me. Definitely worth checking out. I've had it before on my previous cars, the whine/howl would increase/decrease with RPM and was most noticeable when steady around those speeds for sure. In be colder months it was much louder until heating up after driving. Sometimes it was as simple as a fluid flush but sometimes it's worse and it's a worn gear.

This is a good article about it.

http://fuelandfriction.com/weekend-w...rential-noise/

[Jhenka]

Originally Posted by 13M5F10

Sounds like the rear differential to me. Definitely worth checking out. I've had it before on my previous cars, the whine/howl would increase/decrease with RPM and was most noticeable when steady around those speeds for sure. In be colder months it was much louder until heating up after driving. Sometimes it was as simple as a fluid flush but sometimes it's worse and it's a worn gear.

This is a good article about it.

http://fuelandfriction.com/weekend-w...rential-noise/

Damn i was hoping it was something simple.

[Mkai0]

Get it checked out. My dealership now replacing a clutch pack and oil pump, due to my car making weird noises.

[brainblade]

is it a whistling , whining noise? like a distant whistle from behind the dash--almost like a cricket sound that drove me nuts--bmw looked at it many times and said its nothing...never found the solution--I was convinced it was electrical which it was not --they thought it was wastegates....

[kefler]

I have this sound also, maybe 2 or 3 times. Sounds very much like the video.. When the car is cold only. It's constant though regardless of speed and I believe even heard it idling at a light once. The location it comes from is hard to pinpoint.. At best it just seems to be from the middle of the dash. Last time it happened I shutoff all HVAC and played w/ fan speed also, didn't have any effect.

It doesn't bother me at all, so I would only be worried if it was a sign of some problem.

[Jhenka]

Made an appointment with dealer gunna drop of the car tomorrow to see if they can figure it out.

Brainblade,
Its a whining noise like a supercharger winding down except it stays at one constant tone. It's impossible to pinpoint but I did notice that i was able to catch the sound on camera better when the phone was closer to the shifter. I haven't had a chance to record from outside the car to see if its the diff.

Kefler,
The sound becomes more prevalent after the car is warmed up and for some odd reason starts to show up when the engine is under minor load. The most annoying part, with the music off and the windows up cruising at 60 on the highway, that sounds is the equivalent of nails on a chalkboard lol

[kefler]

so weird! I did hear it a few seconds again today.. engine wasn't THAT cold, it had run a few hours before and it's in the 60's here.

It seemed to happen when off throttle @ 50mph or so... I have no idea where it's coming from. rolled down the window and it didn't get any louder.

[Jhenka]

Hey guys, so update on this issue... I got my car back yesterday turns out it was the rear diff. They checked/flushed it and now the sound isn't as pronounced anymore. They said if it gets worse or if i feel something wrong mechanically to bring it back in which case they might need to replace it.

[spenny_b]

Jhenka - hard to tell from your video whether you've got the same sound as mine - some of your observations are similar to mine (cold weather, getting worse) but others are different.

I posted my concerns on this thread a while ago

See the latest update - long story short, BMW have diagnosed it as needing a new gearbox. I'm picking the car back up first thing tomorrow morning, so will have a more thorough debrief with the head-tech then. Thank God for the warranty.

[Jhenka]

Originally Posted by spenny_b

Jhenka - hard to tell from your video whether you've got the same sound as mine - some of your observations are similar to mine (cold weather, getting worse) but others are different.

I posted my concerns on this thread a while ago

See the latest update - long story short, BMW have diagnosed it as needing a new gearbox. I'm picking the car back up first thing tomorrow morning, so will have a more thorough debrief with the head-tech then. Thank God for the warranty.

I'm starting to think i might need a new gearbox as well i've been having a weird jumping sensation every time i let go of the gas directly after acceleration. Like turbo lag but after acceleration. Also from cruising around in sixth gear and suddenly flooring the car seems to confuse the tranny. Not sure if you guys have the same feeling but it takes a good couple seconds before it decides to downshift and go. I attributed both of these things to the catless downpipes i recently installed. I'm going to meet up with a fellow member who also has downpipes to see if his car drives similarly or if i have deeper issues with my car.

On a side note would you mind taking a picture of your work order and forwarding it to me so i can show my service manager?

[TopEnd]

Personally, I would take out your JB4 before the replacement of any major components. They will find any reason to blame after-market parts to deny factory warranty. Even though the JB4 is power-train related and not drive-train related, they will come back and say that the fault was caused by an increase in power directly related to the jb4.

[Eman15]

Originally Posted by Jhenka

I'm starting to think i might need a new gearbox as well i've been having a weird jumping sensation every time i let go of the gas directly after acceleration. Like turbo lag but after acceleration. Also from cruising around in sixth gear and suddenly flooring the car seems to confuse the tranny. Not sure if you guys have the same feeling but it takes a good couple seconds before it decides to downshift and go. I attributed both of these things to the catless downpipes i recently installed. I'm going to meet up with a fellow member who also has downpipes to see if his car drives similarly or if i have deeper issues with my car.

On a side note would you mind taking a picture of your work order and forwarding it to me so i can show my service manager?

Jhenka,

Interested in following up to how your meeting with the fellow forum member went? How did his car drive?

I think I experienced the same feeling you did when my car was coasting. If I took my foot off the gas the car would almost surge, and then on re-acceleration car seemed confused and sometimes would jolt a little before it started going again. Felt like the clutches would pop in/out even though I was in the same gear.

All started when I added downpipes.

Took downpipes out and can still feel it but not as pronounced.

[Igor_M5]

^ Sounds like the typical garbage feeling of a stock non-tuned M5.

[Jhenka]

Originally Posted by TopEnd

Personally, I would take out your JB4 before the replacement of any major components. They will find any reason to blame after-market parts to deny factory warranty. Even though the JB4 is power-train related and not drive-train related, they will come back and say that the fault was caused by an increase in power directly related to the jb4.

What JB4 lol.
I had the tune pulled as as the first measure of troubleshooting.

Originally Posted by Eman15

Jhenka,

Interested in following up to how your meeting with the fellow forum member went? How did his car drive?

I think I experienced the same feeling you did when my car was coasting. If I took my foot off the gas the car would almost surge, and then on re-acceleration car seemed confused and sometimes would jolt a little before it started going again. Felt like the clutches would pop in/out even though I was in the same gear.

All started when I added downpipes.

Took downpipes out and can still feel it but not as pronounced.

I believe the downpipes were the cause of this. I drove a car without them installed and there was much less of a surge if any for that matter.

[SapphireM5]

They are correct its the differential. The reason it makes the noise with you light on the accelerator is because its your pinion bearing/gear which is your culprit. Your pinion gear flexes ever so slightly with the load and the bearing is going causing that loading to change the pitch as it meshes with the ring gear. Unfortunately this will only get worse and more pronounced. Take it back to BMW tell them it needs to be fixed. GL, differential whines are the WORST!