Within Tolerance

[Alpine650]

You can see my history of the vibration/shaking at 60-80 that many others have experienced in the https://www.6post.com/forums/showthread.php?t=1341420 thread. To summarize my 2017 650i xDrive convertible with M Sport Package began vibrating at highway speeds and 1500-2000 RPMs at 35K miles. My car was at BMW of Peabody for 35 out of 53 days. They straightened 7 wheels, sold me 2 new wheels, 2 new tires, and balanced 17 wheels. They did replace the flex disc (Qwibo) after straitening 4 wheels and balancing 4 wheels. But when the disc didn't fix the problem they spent the next month on wheels. My car is under Factory Warranty until June so the wheels and tires were the only part of the car not covered. At one the Shop Foreman told me is "all you need now is 2 new wheels and it will be perfect". That was followed by 2 new tires, more straightening, and more balancing. Then they replaced the Drive Shaft - still no improvement. Finally, they had the BMW Field Service Engineer (FSE) out. I drove with him in the passenger seat and the Shop Foreman from BMW of Peabody in the back seat. Within 5 minutes of highway driving the BMW rep said, "its the torque converter". He then added, "but it's within tolerance"! I basically said wtf! He then drove the vehicle with me in the passenger seat. He added, "its basically the engine breaking in". I said you may be able to to tolerate after driving 10 minutes - I drive highway 1 hour a day - I can't tolerate. Back to the dealer and the rep and shop foreman went to the shop to further evaluate. That night I was told they put a laptop on it driving and there were no error codes. I picked my car up the next morning. The Ultimate Driving Machine is now the Within Tolerance Driving Machine!

[Opie55]

The engine is breaking in at 35K? What do you say when they spew nonsense like this?

[JBF650]

my goodness what a load of tosh and bullshit that dealership is spewing! im sorry to read you are still encountering this... without sounding insensitive , my 650 Coupe is like silk at any road speed i've had it to 240lkms for a few blasts and its fine. If I was allowed to it would be very happy at 160klms all day all night but alas Australia's draconian motorways are limited to 100kls -110klm ..... . no car 'shakes' like you say yours does as a 'bedding in process...... wtf how ridiculous... and at 35K that's well beyond an 'bedding in factor anyway'....

i assume you have tried tyres other than RF? they are horrible things. When i got my 650 i put up with them for about 2 months and then switched to michelin's pilot 4 sports, was like night and day for comfort, noise and handling. in saying that if i recall the RF did vibrate a bit on my car but not to the degree you are saying your car does. two of the them had sidewall bubbles too! so once i got rid of the RF the car was perfect.

with all they said they have done my god .... frankly i cannot think of what else it would be that would be giving you road rolling vibrations.... its very strange and clearly a huge pain in your backside. just for interest's sake can you try say the 19" wheel and tyre package? and see if this changes anything?

[Alpine650]

They know what it is - the torque converter. But they claim it is "within tolerance" and will not replace. I called another BMW dealer and asked for an estimate to replace the torque converter. The SA said while the BMW catalogue does list it as a separate part it is only available with the transmission. $10K job. So I guess the Factory Warranty has a dollar limit.

[JBF650]

Originally Posted by Alpine650

They know what it is - the torque converter. But they claim it is "within tolerance" and will not replace. I called another BMW dealer and asked for an estimate to replace the torque converter. The SA said while the BMW catalogue does list it as a separate part it is only available with the transmission. $10K job. So I guess the Factory Warranty has a dollar limit.

Well that’s extremely unfortunate.... ‘ within tolerance ‘.... I would certainly understand if you decide to sell, I wouldn’t put up with very obvious vibrations at road speed. I’m very sensitive to anything like that in my cars so it’s either something I would have sorted out or sell.
I hope you do get it sorted for you piece of mind
Good luck

[shine775]

Originally Posted by JBF650

Well that’s extremely unfortunate.... ‘ within tolerance ‘.... I would certainly understand if you decide to sell, I wouldn’t put up with very obvious vibrations at road speed. I’m very sensitive to anything like that in my cars so it’s either something I would have sorted out or sell.
I hope you do get it sorted for you piece of mind
Good luck

Take your car up to the speed that it shakes, put it in neutral, shut the engine off. If it still shakes, it's not the engine or torque converter.

[Alpine650]

It doesn't shake when in M/S or Sport mode - only Comfort mode. Doesn't shake when coasting, only under thrust. Here is the BMW NA reply in part to my BBB Complaint, "This vehicle was inspected by a BMW NA Representative who confirmed this is not a torque converter issue. The condition is felt when the torque converter is engaged but that is only because there is a more direct drive through the drivetrain with the converter clutch engaged." That's what I call double-speak. As we were driving the vehicle the first the BMW NA rep said is, "It's the torque converter".

[Mnfamilyguy2020]

I had a very similar issue that eventually presented itself further when the pedal was to the floor and I was transitioning from 95 to 100 miles an hour in a downshift. For me, the root cause ended up being the post cat O2 sensors. The issue manifested itself in slight fuel trim problem that was subtle and created a low rpm stumble and didn’t produce any codes until I absolutely mashed the pedal.

[Walt White Coupe]

The C7 Corvette (I have one that had the problem) 2014 to 2019 had a similar problem with the torque converter. The problem felt like you were driving over rumble strips. If you brought your car to the dealer complaining about the vibration, they would test drive the car and monitor the vibration with a "Picoscope" that would identify the known frequency of the vibration. I don't think there was a "tolerance" limit.

Anyway the solution was to change the transmission fluid to a different fluid that was less hydroscopic which means it didn't absorb water as much as the original fluid. A change in the fluid not only stopped the torque converter shutter but made all shifting notably smoother. It was like a different car after the fluid was replaced. The work order called it "Mobil 1 Synthetic Transmission Fluid". I'm attaching the Tech Service Bulletin that describes the procedure.

I don't know if you are desperate enough to try changing the fluid but I thought I'd let you know what solved mine and other C7 vibration problems.

[Alpine650]

Thanks Walt. Sounds promising. I'm going to talk to the Service Manager about this.

[Alpine650]

Walt I shared your information with the SM and he is looking into. I was surprised to hear that GM and Getrag are the 2 manufacturers for transmission in the 6. Based on your experience I am hoping it is a GM!

[Mnfamilyguy2020]

Originally Posted by Alpine650

Walt I shared your information with the SM and he is looking into. I was surprised to hear that GM and Getrag are the 2 manufacturers for transmission in the 6. Based on your experience I am hoping it is a GM!

I serviced the ZF 8HP70Z auto trans on my 650 this summer. The information I gathered pointed to a GETRAG manual option, M6 variant and the ZF sourced unit I mentioned. There was a lower torque rated unit for the 6 cylinder model, I didn’t find reference to a GM sourced unit.

[Alpine650]

Well maybe changing the transmission fluid to the Mobil Synthetic will work on the GETRAG transmission also?

[Mnfamilyguy2020]

Originally Posted by Alpine650

Well maybe changing the transmission fluid to the Mobil Synthetic will work on the GETRAG transmission also?

I'm fairly certain you have the ZF Transmission in the 650x - ZF 8HP70Z. A GETRAG trans was only offered in the manual 650 - One with a clutch pedal.

The fluid in the ZF 8HP70Z is a synthetic blend. The fluid change was very straight forward for me, I would think the least the Dealer could do would be to change the fluid....

I'm no expert on the GM Transmission in the 2016 Vette. A quick google search presents a very long list of cars/trucks that use the same GM Hydramatic gear box and the class action lawsuit surrounding it that explains the symptoms presented, there doesn’t seem to be any correlation with the 6 series Trans of any kind.

I've done a fair amount of DIY work on Auto transmissions over the years. I'd be VERY hesitant to change the manufacturer required fluid to another for any reason unless the original manufacturer recommended it.

Best!

[Alpine650]

Thanks familyguy. I had email with ZF and they stated the same - don't change from their recommended fluid, it may void Warranty. Big Deal - BMW won't honor the warranty anyway.

[DRock3d]

Mine does the same thing, I've kinda learned to live with it. I don't think there is any amount of straightening that will solve it and I am also in agreement it's something with the transmission. Hopefully you can get the warranty to work out for you, this is a chase I'm not willing to finance out of pocket.

[Simon6666]

Hi,

as mentioned above, if you have the shuddering in high gears on low rpm, the exchange of the two post-cat lambda probes will help. For a test you can simply pull the connectors (the round ones) right under the engine shield. For me the shuddering was instantly gone. Spent before more than 5.000 Euro for try & error repairs, even a new toque converter was mounted without result.

@Mnfamilyguy2020 Your posted helped me very much, after more than 2 years of searching for the error. Thanks a lot!

[Everything Auto NY]

Have you only been dealing with the dealership or have you contacted the corporate office? The dealership wont do anything to help you. However if you are a big enough pain for corporate they will put pressure on the dealerships. From my experience the FSE's are terrible with cars. They know all the cars on paper and seem to be knowledgeable since they have the inside scoop with the actual engineers, but wouldn't be able to actually diagnose a car.

Seriously. Call corporate. DAILY. Eventually they will do it just to make you stop calling. Also if they are trying to wait for the factory warranty to expire, then all you have to do is show all the repair attempts to fix the car. They will find a way to "good will" it.

One last piece of advice. If there is a survey, and they do a poor job, BLAST them on it. Dealerships go out of their way to make sure they don't have bad surveys. If they get to many of them then corporate gets on their ass.

[Alpine650]

Yes. The BMW Field Service Engineer I mention in my initial post was sent out by BMW N.A. He stated it is "within tolerance". I also filed a Complaint with the BBB. Through that I had a couple of conversations with Corporate. Basically the FSE has final say.