530inOK

The Guibo coupling, item #2, and the carrier bearing, item #8, on the driveshaft have been known to cause vibrations. Also the CV Joints on the rear prop shafts.
Glad you have a tech you trust. I'm sure he'll find the problem.
Good luck and keep us posted.

pcy

guibo coupling (mentioned in the above post) is also known as "flex-joint". Due to age, it becomes hard, brittle, and doesn't flex as it's supposed to - causing the vibrations.

grady

Finally got the 550 out of the garage today, and I tried this a few times on the highway. no impact from pressing the brakes at 75 or 80. Vibration lightens a bit, but it is still there.

53K on the odometer.

pcy

while driving (and the vibration is observed), if you move the gear selector to neutral, does the vibration go away?

If the vibration goes away, then the vibration is coming from the drive shaft/flex disc/center support bearing/trans/differential.

Otherwise, the vibration is coming from one [or more] of the suspension components or wheel bearings.

medik13

You must be driving my car...LOL

I have the same problem. I just bought a set of used Iforged wheels and had them refinished because they were pretty dinged up. I mounted brand new Hankook Vetus tires and had everything balanced. Low and behold a vibration at the speeds you mentioned. Since the new wheels had to be trued when refinished, I thought they had not done a good job, so I was thinking it was the wheels. I took them back to the shop and the wheels balanced out perfectly. They also did a runout test on the rim to show me they tracked true. This baffled the shit out of me.

I mounted up my old 124's that I had on prior to the Iforged wheels and again, it was vibrating. Not in the steering wheel, but more like the seat and the rest of the car as you have explained but it was worse with 124's than the Iforged. I never had vibrations before with the 124's. Now I was really confused.

I said, it has to be a problem with the car itself. Once I took of the rear tires, I noticed both lower control arm bushings were torn with a minor amount of grease bulging out. I am going to get around to replace it soon, just haven't had the time. I bet this is the culprit!!!

I too was like you, I am wondering about it not being balanced properly or an alignment needed to be done. Take a look at your suspension components in the rear and I bet you something is worn.

tallers

Grady - I have a 2004 545i that has the exact same problem. My car has 140K miles and I've had the vibration for 2+ years. It happens around 65-70mph. This is my 3rd set of wheels, all brand new with tires. I took my car to the BMW for a recent inspection + emissions and asked that they diagnose and eliminate the vibration. They insisted on rebalancing the wheels and aligning the car. I told them the wheels were new but the did it anyway. I suggested the guibo disc which they said was ok. They wanted at least 2 hours of labor to further diagnose the issue ($250). I'm looking for the possible answer so they can be told what to replace.

Please keep us/me posted!!

Thanks.

antoniom

I have the same exact problem. But the vibration goes away after about 6-7 miles @ highway speed. I feel it from the rear.
Had all my wheels balanced with road force. It's driving me crazy. Can't figure this one out. I'm driving a 2008 550 with msport.

medik13

Check your bushings people...

umichchris

i have the same damn problem! ive had my 19s rebalanced twice now and the vibration is still there @ around 75mph. it drives me fucking nuts! i have a 545i 2004 w/ 55k miles on it...

the problem just came out of now where like 3 or 4 weeks ago and its literally driving me insane. no one in the detroit area has a fix for it. when i go to a tire or wheel shop those assholes only offer three suggestions to fix it....pay them to rebalanced it yet again, buy new wheels, buy new tires...

im trying to learn how to live with the vibrations....but it is too violent, the seats, the sunroof, everything shakes...except my steering wheel and i dont get any vibration in the pedals either. help!

D@rio

AGREED, i have the same problem and mechanic diagnosed control arm bushings (about 100$ for each side).