Car needs a new differential

[Kisenwether]

Had my diff replaced after 5 months of in and out of the dealer. Had grinding on slower turns and also excessive gear lash when shifting gears. Currently going through new break in period but seems to not grind anymore so far.

[Smeargle]

Had my transmission changed around 5k miles due to how 1st gear would engage sometimes, and then when moving it would just violently smash the car back into neutral(with the clutch out...). When I got the car back they said they also changed my diff due to a sound they heard. Was under warranty so I didn't question it but this thread is very interesting. MY18 6spd btw

[YasMarinaBlue]

Hi everyone. I have this same high pitch whine noise. I have a 2017 BMW M4 (DCT). The dealer actually agreed that they heard the noise and that it was coming from the rear differential. I think the regional service tech overruled them because they told me it is "a characteristic of the car" and as such is not serviceable. It would be great if someone can send me their service records showing the problem and what work was done. Maybe I can convince them if I have some documentation.

[swagon]

Originally Posted by YasMarinaBlue

Hi everyone. I have this same high pitch whine noise. I have a 2017 BMW M4 (DCT). The dealer actually agreed that they heard the noise and that it was coming from the rear differential. I think the regional service tech overruled them because they told me it is "a characteristic of the car" and as such is not serviceable. It would be great if someone can send me their service records showing the problem and what work was done. Maybe I can convince them if I have some documentation.

hey, could you please explain what the noise is and how/when it occurs?

[YasMarinaBlue]

2017 BMW M4 with 30K miles. I have this annoying high pitched whistle noise at highway speeds.The noise starts after I reach 2000 rpms. It is amplified when I press on the gas peddle but it remains even when I am not giving it gas. Again when the engine rpms drop below 2000 rpms the noise goes away. This is why you don't hear it at speeds below 65mph (unless you decide to drive around in a lower gear). The noise makes driving the car almost unbearable. The dealer said it is a characteristic of the car and will not fix it even though they said the noise is coming from the rear differential. The first link is a video showing the rpms but the noise is hard to hear on it. In the second video I hold the camera near the floor and you can see my foot pressing the gas pedal and can clearly hear the noise. It is definitely louder near the floor which makes sense if the differential is to blame. Around 40 seconds in the noise gets really loud in the second video.

https://drive.google.com/open?id=11o...Ie7TsI7lL79Hsx

https://drive.google.com/open?id=1ME...xJDpG7yE5Xxo8h

[DocL]

Bringing this thread back to life. I noticed a few weeks ago a drone/whine from the rear of my car starting at 55mph in 4th, 5th, and 6th gears. With light throttle it gets louder and then off throttle it goes away. Brought the car in last week for an oil change and asked for the sound to be investigated. First they said they didn’t hear it, then the SA took the car for a drive and he heard it and have the shop foreman listen. I was told they replaced some bearings between the driveshaft and diff, but the sound was still there. They ordered and replaced the same parts again and said the sound is still there. Now a week later they are going to get a new differential installed.

I don’t know if I should be worried about this happening again. My 2018 has 32k miles and I’ve never had to replace a differential in any car before. My car is all OEM.

[aswy6]

Would like to take an opportunity and also ask a question here. I recently had diff fluid changed at the shop with all OEM stuff and right after i started noticing a slipping sound from the diff on tight turns. In the morning its a very momentarily sound but when making a sharp turn and letting off the throttle mid turn, it would make that sound every time. Has anyone experienced something like that when it only does the sound when releasing the throttle mid turn?

[09carreras]

Originally Posted by DocL

Bringing this thread back to life. I noticed a few weeks ago a drone/whine from the rear of my car starting at 55mph in 4th, 5th, and 6th gears. With light throttle it gets louder and then off throttle it goes away. Brought the car in last week for an oil change and asked for the sound to be investigated. First they said they didn’t hear it, then the SA took the car for a drive and he heard it and have the shop foreman listen. I was told they replaced some bearings between the driveshaft and diff, but the sound was still there. They ordered and replaced the same parts again and said the sound is still there. Now a week later they are going to get a new differential installed.

I don’t know if I should be worried about this happening again. My 2018 has 32k miles and I’ve never had to replace a differential in any car before. My car is all OEM.

Let us know how it goes. I have the same problem and a new diff didn't fix it in my 2018.

[DocL]

Originally Posted by 09carreras

Let us know how it goes. I have the same problem and a new diff didn't fix it in my 2018.

My issue has been completely resolved. No noise, and the vibration that I felt and heard is gone.

Sorry that you are still having the problem.

[WarMachineM3]

Originally Posted by YasMarinaBlue

2017 BMW M4 with 30K miles. I have this annoying high pitched whistle noise at highway speeds.The noise starts after I reach 2000 rpms. It is amplified when I press on the gas peddle but it remains even when I am not giving it gas. Again when the engine rpms drop below 2000 rpms the noise goes away. This is why you don't hear it at speeds below 65mph (unless you decide to drive around in a lower gear). The noise makes driving the car almost unbearable. The dealer said it is a characteristic of the car and will not fix it even though they said the noise is coming from the rear differential. The first link is a video showing the rpms but the noise is hard to hear on it. In the second video I hold the camera near the floor and you can see my foot pressing the gas pedal and can clearly hear the noise. It is definitely louder near the floor which makes sense if the differential is to blame. Around 40 seconds in the noise gets really loud in the second video.

https://drive.google.com/open?id=11o...Ie7TsI7lL79Hsx

https://drive.google.com/open?id=1ME...xJDpG7yE5Xxo8h

What did you do? I'm having this same issue. It's much more audible now than before.