Hi.I have a strange noise/hum/vibration when accelerating.It is characterized by only being in high gears 4/5/6 right between 1800-2000rpm.Also only happens when I accelerate the car hard.On smooth acceleration it is gone.Noise or whatever it is there, I define it as a loud rumble heard from the middle of the passenger compartment to the rear (I can't be sure if it is heard from there exactly). In an attempt to solve the problem, I have replaced the rubber frame of the cardan, hanging bearing, pad of the gearbox, muffler pads, as I have also checked the engine pads - they hold vacuum, the bridge and differential pads are healthy. The oil in the gearbox and differential has been replaced with Ravenol. The car is an e61 3.0d with a manual gearbox. If anyone has an idea where to look for the problem, PLEASE write. Thank you in advance.

 

Which car and year do you have. E61 30d tells us nothing

 

I will give a stab in the dar and say check flex disc.

 

Sorry, my bad.The car is 525d LCI 2008y manual transmission.Here is a short video if you can hear the noise.Thank you.

 

Yeah hard to tell from the video. Has something been done to the muffler? I would check the flex disc and around the pipe but that sound after the first pull sounded like it was inside the cabin. Don't know if that's what you were talking about

 

No, nothing has been done to the mufflers other than changing the pads. The noise when shifting is a side spray noise in the trunk. Is there a way to check the flywheel without removing it? There are no ignition and shutdown noises coming from it.

 

I was also going to say check the flex disc.

 

I don't think it's the fly wheel. Check the flex disc to see if you have movement

 

As a precaution, I changed the flex disc, thinking that the problem was caused by it. I also changed the bearing on the drive shaft.

 

Do you have a lift available. You can lift it in the air and put it in drive to see if the issue is coming from below.