[88atlas07]

Fellow Bimmer enthusiasts, I need your help.

Car- 07 e92 335i 119k miles

Im chasing a driveline vibration for the last 20k+ miles and cant pinpoint where its coming from. Symptoms are a rhythmic vibration that can be felt and heard through the chassis of the car, but only under load, starting at approx 55mph but seems to disappear around 80mph. I first thought it was was the guibo or csb so replaced both of those and that didnt help, so ordered a new driveshaft from the dealer thinking possibly bad U joints, which came with a new guibo and csb already installed and that didnt help either.

Tires are balanced and zeroed out as of yesterday- still no change. Alignment hasnt been done in about 15k miles but that didnt change the vibration either the last time I had it done.

What I have replaced:

Complete driveshaft including guibo and csb
Subframe bushings (yellow poly)
Tires (Michelin AS3 stock size for sport package on style 189 rims)

The fact that it does it ONLY under load leads me to believe that it cant be the wheels, so only thing I can think of would be the wheel bearing, diff bushings, or worst case the diff. The diff has fresh fluid, as well as the trans, no whines or knocks from either.

Someone please point me in the right direction. I have a 25 year old 5 series that rides smoother then this thing.

Thanks

[j1gilles]

I had the same issue.. Make sure you don't have a bent rim.

[Donalde3]

Sounds like bent rim or diff bushings. Possibly tie rods or control arms

[YRAGAEL]

If it's only vibrating under load, that kinda rules out a wheel issue. Since you've already done the driveshaft, it could possibly be a CV joint on one of the rear axles.

[88atlas07]

Took the car into a reputable tire place and had everything re-balanced and turns out the pass rear wheel is slightly bent. He was able to balance it in a way that its a lot better then it was before, but still vibrates. Now just debating whether to buy a new wheel from the dealer or find a place that can straighten it.

[j1gilles]

Just have it straightened...

[88atlas07]

Update- I bought a new rim and had the dealership swap over the tire and sensor just to make sure it was balanced correctly... there is still a slight vibration. The rhytmic hum is still there too.

Next on the list are diff bushings, already have the purple poly bushings sitting on my desk so in the next few weeks those will go in. If that doesnt solve it then im done and will live with it, I'm not replacing axles at $500 a side

[Duperstar]

Get remanufactured ones they are like $125 a side. I had to do the fronts on my xi. Same thing, vibration on accel only.

[88atlas07]

Originally Posted by Duperstar

Get remanufactured ones they are like $125 a side. I had to do the fronts on my xi. Same thing, vibration on accel only.

I will look into that, thanks

[88atlas07]

Another one for you guys-

This week I will be replacing the drivers side axle, bought new from the dealer for an arm and a leg, as well as doing the M3 control arm upgrade for the front end. I installed ECS spacers 12mm front and 17.5mm rear and noticed a new vibration, much worse than the one before and this one isnt acceleration based, its vehicle speed dependent. This occurs at exactly 105mph (autobahn) and gets worse the faster I go, and its so bad that the nav screen looks like im riding on rumble strips.

I didnt notice the severity of this before but im sure the problem was there and the spacers just exaggerated the problem. I put the car on blocks and ran it to 120+mph mph and could see that the drivers side tire had an up and down vibration to it. I could feel the vibration in the chassis starting at 80mph and progressively get worse as speeds increased

I tried this again without the spacers and at exactly 105mph the same thing, just less severe.

Does this sound like the cv axle, or wheel bearing? No noise coming from the wheel bearing so didnt think it would be that. Im going to keep throwing parts at it until I figure this out, but what about rotors? I checked the hub runout and thats within spec but could the rotors cause a vibration? Disk area is good, but the disks drum where the hand brake pads grip seemed out of round.

All wheels are straight and balanced.

[07tundra]

Have you checked your trans mounts?

[88atlas07]

Originally Posted by 07tundra

Have you checked your trans mounts?

Yes. They seemed fine. I have a set of black UUC mounts that I had in for a while but they created too much NVH so put the stock ones back in. Ill swap them out and see if it changes anything when im doing the axle Tuesday

[88atlas07]

In the process of doing the Powerflex diff bushings, and cant figure out which side of the bushing the load washer goes on. Anyone know? Also, the axle that the dealership sold me has a torn boot right out of the box, so thats going back tomorrow and I'll have to wait a few days for a replacement.

Edit- Nevermind, all washers face the front of the vehicle

[88atlas07]

Replaced the drivers side axle and diff bushings and vibration is gone.

In total, I replaced
-driveshaft
-bent wheel
-axle
-diff bushings

All had an impact on the vibration but I'm pleased to say it rides like a BMW again. Just in time for the Nurburgring in two weeks. Thanks for the ideas fellas...appreciate it.

[ccourteau82]

Wow that was quite the journey... Glad you got it all sorted out...