Steering wheel vibration (B...M...W)

[Mr Filipov]

Hello all, long time no post for me. I tried to get an answer on the BMW forum, but no luck on there. Guess people are not as friendly as here.
I was wondering if someone has a general idea as to where I can look to sort my problem? Any help is appreciated of course.

Apologies for the long thread, please bear with me.

I have got a bit of an issue with my GT. Now, to start off it is on the 20" wheels with run-flats, they are on the proper pressure as displayed on the door card at 2.5 bar on the front. Wheel alignment has been done at main dealer after it got done at an independent, which I will not mention as I have not had a good experience with them, and they did not do the best job.

What I have noticed since getting it all done is a bit of a vibration/very slight wobble coming from the wheel, and can be felt through the bottom of the seat as well at motorway speeds at around 80. Below that it seems to settle down and cannot be felt nowhere near as much, if at all. That said, I did not notice it at all before, but you don't notice what you're not looking for. May have been there, just never paid enough attention at first. The first independent recommended that the thrust arm bushes need changing (2017 car with 45k on the clock, I'm the second owner), but upon inspection at BMW main dealer they advised that is nonsense (I have known that particular independent to list work that does not need doing, but that is another point).

I am fairly certain nothing on the suspension part needs doing. Where should I be looking to see if there is a problem or if it is just because of the big wheels and run flats? I had a 2014 GT right before this one with 19" and never noticed this (again, maybe never looked, or it may not have been an issue due to smaller wheels).

I would be very grateful for any suggestions, even including bits on the suspension/steering as to trying to track down the potential problem. I have not done wheel balance yet, but with the current state of affairs, I will not be able to do so any time soon. This is however on my list of to do once everything is back to normal.

If you need any other information feel free to ask.

Many thanks

 

[LostKiwi]

Take the wheels off and have them put on a balanced. Check for out of round (vertical wobble of the tread and rim) and out of true (lateral movement of the wheel rim and tyre). Either will cause vibration.
You could also have an out of balance propshaft, worn gearbox mount, worn propshaft couplings, worn diff mounts etc.

 

[dry run]

If noticable under braking - could be brake disc?

Wheel balancing - cant remember if you said that had been done.

People try rotating the wheels (left to right and seeing if that makes a difference).

I'm sure others will have more ideas

 

[Blobcat]

Wheel out of shape, would be my first point of call

 

[Mr Filipov]

Thanks for all the input guys, it really is much appreciated. Engine mounts, gearbox mount etc everything is checked over. There is no vibration during breaking, so I am fairly certain I can rule out discs.

Balancing of the wheels is on my to-do list, but in the current state of affairs it is not going to be possible. The car doesn't get much use as of right now anyway.

Buckled wheel is my worst fear, because along with the extensive spec list on the car itself, it also sits on quite expensive optional wheels as well haha. Currently just gathering a list of possible causes.

Just out of curiosity @LostKiwi how would an out of balance propshaft cause vibration at the wheel? Genuinely interested to find out

 

[LostKiwi]

Not so much at the wheel but a general vibration.

 

[Mr Filipov]

Ok that makes sense. My hunch also suggest that 20 inch wheels on run flats at the correct pressure might be a smidge too much. A simple test that I can do at no outlay to me is lower the pressure a smidge and see how that goes. Say 2.5 bar down to 2.3. Any ideas as to that is worth a try?

 

[oigle]

Post number 2 is best bet.

Ian.

 

[Mr Filipov]

Cool, thanks for all the input guys. Will action as soon as some normality is restored.

 

[malcolm E53 AMG]

Run flat tyres are awful things I’m guessing they are the second set at 45k miles. My 14 plate 435i was bought with 6k miles on the clock 18 months ago obviously with the original tyres still fitted @ <20% worn, the tyres had hardened (over 4 years old) and the ride was awful including a serious vibration on some surfaces so as soon as finances allowed they were changed for Michelin standard tyres, the ride is much improved and vibrations problems have disappeared.

I suspect this may be your problem

 

[Mr Filipov]

@malcolm210 I suspect that may well be the case. The previous GT was fine with run flats but it was on 19s and there was a bit more meat on it. I like the convenience that they offer, but it is too much of a compromise on the ride at 20”.

May well consider going this route once budget allows at around £1k a set haha.

 

[John Laidlaw]

If you’ve time on your hands now until post 2 is achievable it’s worth elimination of the obvious. It won’t be suspension parts unless the car dropped over a cliff dukes of hazzard style!
Anyway check the tyres all over visually, if necessary taking the wheels off one at a time, might be an egg on the inner wall or delamination- what brand?
Also any weights- still there?

 

[Mr Filipov]

If you’ve time on your hands now until post 2 is achievable it’s worth elimination of the obvious. It won’t be suspension parts unless the car dropped over a cliff dukes of hazzard style!
Anyway check the tyres all over visually, if necessary taking the wheels off one at a time, might be an egg on the inner wall or delamination- what brand?
Also any weights- still there?

Hello John, unfortunately my drive on a slope and I’m not overly keen on 2 and a half tonne dangling about haha. I will have another look again. Have already looked at them but without the proper gear that is all I can do.

Weights are there and it doesn’t look like any have fallen off. Tyre condition seems fine, they are pretty new (in the respect of tyre wear). Car has sat around for 6 months in showrooms before I purchased so I am not ruling out a flat spot.

If I can get it somewhere on level I will take off each wheel and visually inspect for cracks and buckles on the inside. All looks good from the outside at least.

 

[RhodieBill]

The other thing you could try is if you know someone with the same car, or simular car with simular size wheels that are known not to wobble/vibrate and swap out just the front 2 first and test. If the wobble has gone you know where to look at least. If it still wobbles/vibrates swap the rears aswell and test. If now it doesn't wobble you know it is the rears that are the problem. If it still wobbles then at test you know it's not your wheels with a certain amount of certainty and look elsewhere.

Anyway that is the easy way and costs nowt except maybe a beer for the donor.....

 

[Mr Filipov]

@RhodieBill Well funny you should mention that. I am looking to swap wheels etc but just try a different car with the 20" wheels. A friend just bought one with that size wheels. Problem is it happened just before we went into lockdown. Once free movement has been restored he is happy for me to give it a go myself so I can compare. Thank you for the suggestion

 

[RhodieBill]

@RhodieBill Well funny you should mention that. I am looking to swap wheels etc but just try a different car with the 20" wheels. A friend just bought one with that size wheels. Problem is it happened just before we went into lockdown. Once free movement has been restored he is happy for me to give it a go myself so I can compare. Thank you for the suggestion

You're welcome.

 

[Mr Filipov]

Hello all, just a quick update. I may have spotted the problem at hand. The NSF has no balance weights on it.

That probably explains it all. In my mind there is no chance that a 3 year old alloy with a tyre that would have been changed once will have the perfect balance off the bat. I will pop over to an open garage during the week and sort it out.

 

[John Laidlaw]

Thought that may be an issue , hopefully you’ll get sorted

 

[Mr Filipov]

Hopefully will be able to get it done tomorrow or day after and will update how it goes.

 

[Flyinspanner]

You could make a homemade check for flat spots/wobble. (In lieu of a DTI gauge)
Use a skewer, and either a piece of wood or some bricks so you can securely point the tip to the edge of the rim (jacked up).
Gently spin the rim by hand and see if the distance between tip of skewer and rim stays constant.