Rhythmic Vibration

[thebmw]

When driving, especially in higher speeds, I'm noticing rhythmic vibrations from what seems to be the drivetrain. At 80 mph, the oscillations of the vibrations are spaced out around one second. That oscillation goes down as the speed goes down. This seems to be coming from the drivetrain. It is not coming from the wheels. There's no way that it could since it is once a second at 80 miles an hour. It seems to go away when I accelerate and come back when I cruise.

The vibration feels like going over very small rub strips on the road. For reference, the car is a 650 GC xDrive. I'm wondering if it has something to do with the transfer case or guibo joint? Or maybe differential? It just seems odd at the very exact spacing between the rhythmic vibrations (which is a great name for a band LOL).

[arucano]

have you had your wheels balanced lately? Strut bushing vibration is generally constant at a specific speed.

[thebmw]

Originally Posted by arucano

have you had your wheels balanced lately? Strut bushing vibration is generally constant at a specific speed.

It is happening with the summer and winter tire/wheel set. All were balanced before mounting.

I will look into the strut bushing. Never heard or thought of that. Could it be CV joints or anything else with the entire suspension?

Can the differential or transfer case cause rhythmic this vibration? It feels like it is coming from behind the driver, not in front.

[arucano]

drivetrain components will produce a constant "tone / vibration" that is proportional to speed. check if it is engine rpm dependent or drivetrain (gearbox output speed dependent to narrow it down it you think it is the drivetrain. if it is the suspension, it will generally happen at a certain speed.

[v1tal]

Hey, any update on the vibration? I have a 2-door 2015 640d with the same odd vibration.

You start feeling it at motorway/highway speeds around 60-80mph and the vibration is 2seconds vibrating and then 2 seconds almost no vibration which is odd.

I replaced guibo, have all new tyres and done wheel balancing but nothing helped

[thebmw]

Originally Posted by v1tal

Hey, any update on the vibration? I have a 2-door 2015 640d with the same odd vibration.

You start feeling it at motorway/highway speeds around 60-80mph and the vibration is 2seconds vibrating and then 2 seconds almost no vibration which is odd.

I replaced guibo, have all new tyres and done wheel balancing but nothing helped

After reading various posts, I was thinking it could be giubo. But I have now at time to get it replaced or checked out. After your post, I might be back at square one. It does seem to have something to do with the drive train and something is vibrating. Maybe a bushing or connection between drivetain and something else?

[v1tal]

Honestly I do not know what could be the issue here. I've seen it being posted by many people, but never saw a concrete solution

[racer2086]

Generally for a vibration that is coming and going like that, you are dealing with 2 vibration sources at different frequencies. The different frequencies cancel each other out and add to each other based on the overlap of the waveforms.

Tires would be the most likely for one of them. You need to find a local shop that does road force balancing. It took me many shops over the years, but I finally found one that does it right (not just says they do it) and it makes a huge difference. Most places don't take the time to measure the run out, mark the rim and tire, and then remount the tires in the correct orientation. BMW would though.

Beyond that it will take some diagnostics to narrow down the source.

[thebmw]

I will be getting it checked out this week. It could be a combination between the driveshaft center support bearing and the giubo. I don't think it is the wheels as I have swapped them out with different wheels/tires with no change. And this feels totally different and feels like it is coming from almost underneath me (right where the drivetrain is.

The rhythmic waveform is shortening in oscillation delay, implying to me that the problem is slowly getting worse.

[Alpine650]

Try putting the transmission in M/S (pull the shifter knob toward you). Or try driving in manual mode and see if it still does it. I had the same problem. 2 new wheels, 2 new tires, 12 balanced wheels, replaced quibo, replaced drive train. In shop for almost 2 months. BMW engineer came out to drive it with me on the highway. Within a minute he said it is the torque converter, but it is within spec.

[Robs335iproblems]

Anyone have a solution for this? I've been battling it with my F12. Tires road force balanced countless times, cleaned off the hub and rotor to make sure there wasn't any rust, swapped tires from different cars, replaced control arms, sway bar bushings, sway bar links and nothing seems to be making any difference. I've never had an oscillating vibration before where it comes/goes every 2-3 seconds. What about the struts? Could bad EDC struts cause issues? Maybe there's a problem with the valves and they continually try to adjust which creates a sinusoidal vibration. If anyone has input, it would be great, however, I'm going to see if I can watch the EDC valve voltage as I drive. I'd think that could indicate if there's an issue. I feel this has to be due to electronics in the vehicle trying to adjust to inputs, over adjust then under adjust as opposed to an out of balanced tire.

[thebmw]

Originally Posted by Robs335iproblems

Anyone have a solution for this? I've been battling it with my F12. Tires road force balanced countless times, cleaned off the hub and rotor to make sure there wasn't any rust, swapped tires from different cars, replaced control arms, sway bar bushings, sway bar links and nothing seems to be making any difference.

Assuming your rhythmic vibration is not coming from your significant other while in the car with you, it may be coming from driveshaft vibration due to giubo/flex disc cracks (which is the same issue I had).

[nmirza]

Have you tried coasting in 'Neutral' when travelling at speed? Might indicate issue with transmission a bit more clearly?

[Nice95gle]

Originally Posted by Robs335iproblems

Anyone have a solution for this? I've been battling it with my F12. Tires road force balanced countless times, cleaned off the hub and rotor to make sure there wasn't any rust, swapped tires from different cars, replaced control arms, sway bar bushings, sway bar links and nothing seems to be making any difference. I've never had an oscillating vibration before where it comes/goes every 2-3 seconds. What about the struts? Could bad EDC struts cause issues? Maybe there's a problem with the valves and they continually try to adjust which creates a sinusoidal vibration. If anyone has input, it would be great, however, I'm going to see if I can watch the EDC valve voltage as I drive. I'd think that could indicate if there's an issue. I feel this has to be due to electronics in the vehicle trying to adjust to inputs, over adjust then under adjust as opposed to an out of balanced tire.

This may be a long shot. But make sure that none of your calipers are sticking.
I was having the same problem with my 850. And, it turned out to be a bad brake caliper.

[Robs335iproblems]

Thanks for the replies.

I've checked my rotors/pads/calipers. All ride smoothly and no issues/rubbing/sticking, etc.

I have tried to shift into sport mode, punching the RPM up and seeing if there were any change, potentially being related to the engine speed/engine mounts, but no difference there. I'll try to drop it into neutral, but that'll be doing 80mph+ so I'll only have a short time to see if it dissipates. I'll check fluid level in the tranny also, to see if somehow, that's contributing to the issue

I've checked the center support bearing and pre-load, along with both the Guibo near the transmission and have replaced the Guibo at the rear differential (older F12's had two of them). I just replaced the differential bushing, which I was hoping would solve the problem, but it did nothing.

If I finally get to the root of the problem, I'll post my solution in order to help the community.

[Robs335iproblems]

So the issue may have been resolved. I'm hesitant to say anything has been fully taken care of until I drive the car for a while, however, upon first highway drive today, the car feels totally smooth.

Resolution...Replaced the drivers side EDC Strut. Afterwards, I used ESYS to VO code the ICM, ICM_V and all four EDC strut/shock modules (RK [a5, a6, a7 a8]). I don't know if redoing the VO coding actually did anything, however, I figured that it would have essentially reset all of the ECU's back to factory settings and also assumed that it woudn't hurt.

Driving from 0 to 85mph, varying the speeds, up/down inclines, on/off the accelerator, and in all cases, the car was smooth.

I might have gotten lucky as I did the driver side first by total luck, but if it didn't work, then I was going to try the passenger side. Regardless, the replacement strut did the job.

[Andresschmal]

Hi, I'm having the same issue with my 428i 2016, this is the first time I'm hearing struts were the solution, I actually have some pretty bad ones (duralast) that came from the last owner but I was waiting on fixing this vibration issue before changing them lol, just before I pull the trigger, did yours vibrated on the front/wheel section? I can hear a 2 per second vibration coming from that area at specific speeds, 40, 50 and 75 mph, anything out of that and the vibration disappeares. It's kinda like womb womb womb and I can feel a slight vibration coming from the front.

Here is a link with the sound I managed to record.

https://youtube.com/shorts/PVGjIzPD35w?feature=share

[faxfan2002]

Propshaft coupling? Vibrations at higher speeds - had mine replaced and it went away.

[Andresschmal]

I did think about that one too, did yours made a humming noise/vibration only at specific speeds and disappeared when driving fatser or slower than that specific speed?

[Robs335iproblems]

My issue has returned (or maybe never really went away?). I may look at the passenger strut, but I hate throwing parts at cars without actually diagnosing the issue.

I have no noise. I do know that noise, humming, etc. typically means wheel bearing, as I've had those replaced on other vehicles in years past. My car runs completely quiet, so it's not that.

I did check my tranny fluid level and had to add about 1/2 quart. Not sure that solved anything either.

It's the oddest thing since the car will drive smoothly for the 1-2 seconds as the oscillation comes/goes. So I highly doubt it's wheel/tire/rim related. Otherwise, it would happen all the time. I've had out of balance wheels and I know what that feels like.

I checked the drive shaft and it feels solid. No apparent issues with the u joint connection that I can see.

I am at a complete loss. Interesting enough, I have found other posts in other forums, so this happens on other vehicles. I can't seem to figure out what/where the problem is coming from which makes this absolutely frustrating.

And with a highway drive to/from work, it continues to remind me that there's a problem that I can't solve. To some extent, that's the most frustrating since I don't like to lose.

For other info, I have 20" tires on the car, so I might switch to 19" to see if that has any impact to either the timing of the oscillation, length, speed or otherwise.

Additionally, my 650 is rear wheel drive, so there's no axle's in the front or transfer case, etc.

[Northshore]

Have a very similar problem on the 2014 650 that I just picked up.
Any 'more than slight' uphill at a constant speed (cruise on) will make the rhythmic vibration at roughly the intervals (a second or so) that the OP spoke of. I have been told by my shop that tension struts are starting to ooze and the forward giubo, although not critical, should be replaced. The tension struts along with a handful of other things are getting dealt with when the car goes in in two weeks and the giubo will get done at the next oil change and that should be mid July. If either of those cure the issue, I'll report back.

[Robs335iproblems]

@Northshore, please post any results.

I've replaced both the control arm/tension strut and lower wishbone along with the sway bar and sway bar end links. No changes.

I've replaced the rear GUIBO with no change either.

As I've thought about everything that's rotating, Engine, Transmission, Wheel Bearings, Drive Shaft, Rear Axle, Wheels, I feel as if the drive shaft is the only thing left.

My engine is new and the mounts are good. The engine is solid in the bay and when I rev the engine while in park, it sits nearly still. I know bad mounts will allow the engine to move when revving and you'll feel vibrations it in the car at idle.

The transmission is good. I've dropped gears, revved the engine and put the car in neutral while driving and there was no change to the frequency of vibrations, so I'd say it isn't related to transmission speed, the torque converter, etc.

The wheels are good. I've swapped wheels and the vibration is still there.

The wheel bearings are good. I've had bad bearings and the noise is always noticeable when they are going bad and my car is quiet when driving.

The rear axles seem to be good, but who knows. I've put the car on a lift and let the wheels rotate in drive and the axles seems to spin fine. I've replaced the rear differential bushing as that is known to cause vibrations, but no change.

The driveshaft seems to be the only thing left. The shimmy/vibration is felt inside the car, not the steering wheel. How/why it's bad, not sure as it feels good and the u-joints seem tight. While it's a pain to replace (need to drop the exhaust), I might grab a used one on eBay (which are surprisingly inexpensive) to see if swapping it out, solves the issue. If not, I'm out of ideas.