Vibration at high speeds problem

TKB

Active Member
Jun 20, 2022
7
3
So on November I had to change the oil/filters on my Formentor so I went to the dealership and asked to swap my tires to winter tires while I'm there. Immediately after changing the tires, when I got on the highway heading back to home I felt huge vibration at around 100km/h. The vibration could be felt mostly through seats, floor, door and center console. It worsened when I went even faster. At 120km/h it could be felt at the steering wheel as well.

I went back to dealership next day, they rebalanced my wheels, but the vibration persisted! The dealership said I might have bent a wheel and should check my wheels.

I was very sceptical about such a suggestion, because the vibration started after changing the tires. But alright I went to some local wheels service to check if I had any damage to wheels and even did straighten one of the wheels that was a little bent. Guess what, the vibration persisted.

I then went to rebalance my wheels in independent service and when the vibration persisted I even tried the road force balance with HUNTER GSP9700. Vibration became more subtle, but still remained!

In one of the services they noticed that the front left wheel bearing of Formentor was different size from the original Cupra rims center bore. Apparently the rims have center bore size of 57,1mm, but the wheel bearing size was about 3 mm less. So the guys there explained me that this might be an issue as the wheel isn't perfectly centered. They even showed me that there's movement in unbolted wheel and they told me that it shouldn't be like that at all.

I even communicated with the shop where I purchased the winter tires (Hankook evo3) thinking that maybe the tires could have been faulty. The tire shop was very responsive and I ended up swapping my winter two more times. Apparently the tire shop admitted that the Hankooks I had might be the problem when they inspected them. Now I'm having Goodyear Ultragrip performance tires. The car vibrates less now, but it is still very annoying especially when I have to go on a longer drives on highways for more than an hour.

I went back to dealer to possibly troubleshoot the vibration there and also asked about the difference in sizing of rims center bore to wheel bearing, but they responded that the Formentor wheels have conical seats so there's no problem if the unbolted wheels can be shaked a bit, because apparently conical seats are supposed to center the wheel. And they of course told me that car looked fine and they didn't notice any vibration while testing out my car. When I asked how fast did they go they responded that they only tried it out in the city and never got to high speeds when I specifically told that vibration happens only on highway speeds... They put 18 inch Cupra wheels from their demo car on my Formentor to test within the weekend if the vibration persists. I tried it out and the vibration at high speeds are still there. Its not huge, but I can definitely feel it. It even gets very obvious at 120km/h. It's kinda frustrating at this point, because I have a feeling that the dealership won't be very helpful as they do not believe there is vibration at all...

Has anyone had anything similar with their Formentor? Maybe you could give any inputs to what might be the problem? Could it be that the 19 inch rims tend to "sit in" and change shape and are sensitive to swapping places and the dealership mixed up the places of the wheels? I remember reading something like that somewhere. I don't know. But if the wheels were the problem why would I feel vibration with the 18 inch Cupra rims aswell...? :(

Any inputs will be appreciated.
 

pkaps

vz310
May 10, 2022
289
135
When my vz is fully loaded, at highway speeds and accelerating from abt 100 to 140 I get sometimes a feeling of slight vibration on my seat but nothing annoying and it doesn't last. When I'm alone or not loaded I cannot feel anything. Since it has to do with floor/seat vibration it most likely is related to rear wheel balancing but being mostly unnoticeable I do not even think of trying to address it, only if in time it gets worse and annoying although so far and for 14000+ kms is still the same.
 

pkaps

vz310
May 10, 2022
289
135
No, got used to it at first, then rotated the tires at 20000 and having them balanced again, it is now almost non existent.
 
Oct 9, 2024
1
0
So on November I had to change the oil/filters on my Formentor so I went to the dealership and asked to swap my tires to winter tires while I'm there. Immediately after changing the tires, when I got on the highway heading back to home I felt huge vibration at around 100km/h. The vibration could be felt mostly through seats, floor, door and center console. It worsened when I went even faster. At 120km/h it could be felt at the steering wheel as well.

I went back to dealership next day, they rebalanced my wheels, but the vibration persisted! The dealership said I might have bent a wheel and should check my wheels.

I was very sceptical about such a suggestion, because the vibration started after changing the tires. But alright I went to some local wheels service to check if I had any damage to wheels and even did straighten one of the wheels that was a little bent. Guess what, the vibration persisted.

I then went to rebalance my wheels in independent service and when the vibration persisted I even tried the road force balance with HUNTER GSP9700. Vibration became more subtle, but still remained!

In one of the services they noticed that the front left wheel bearing of Formentor was different size from the original Cupra rims center bore. Apparently the rims have center bore size of 57,1mm, but the wheel bearing size was about 3 mm less. So the guys there explained me that this might be an issue as the wheel isn't perfectly centered. They even showed me that there's movement in unbolted wheel and they told me that it shouldn't be like that at all.

I even communicated with the shop where I purchased the winter tires (Hankook evo3) thinking that maybe the tires could have been faulty. The tire shop was very responsive and I ended up swapping my winter two more times. Apparently the tire shop admitted that the Hankooks I had might be the problem when they inspected them. Now I'm having Goodyear Ultragrip performance tires. The car vibrates less now, but it is still very annoying especially when I have to go on a longer drives on highways for more than an hour.

I went back to dealer to possibly troubleshoot the vibration there and also asked about the difference in sizing of rims center bore to wheel bearing, but they responded that the Formentor wheels have conical seats so there's no problem if the unbolted wheels can be shaked a bit, because apparently conical seats are supposed to center the wheel. And they of course told me that car looked fine and they didn't notice any vibration while testing out my car. When I asked how fast did they go they responded that they only tried it out in the city and never got to high speeds when I specifically told that vibration happens only on highway speeds... They put 18 inch Cupra wheels from their demo car on my Formentor to test within the weekend if the vibration persists. I tried it out and the vibration at high speeds are still there. Its not huge, but I can definitely feel it. It even gets very obvious at 120km/h. It's kinda frustrating at this point, because I have a feeling that the dealership won't be very helpful as they do not believe there is vibration at all...

Has anyone had anything similar with their Formentor? Maybe you could give any inputs to what might be the problem? Could it be that the 19 inch rims tend to "sit in" and change shape and are sensitive to swapping places and the dealership mixed up the places of the wheels? I remember reading something like that somewhere. I don't know. But if the wheels were the problem why would I feel vibration with the 18 inch Cupra rims aswell...? :(

Any inputs will be appreciated.
I have exactly the same problem, vibration starts exactly at 100 km/h, and increases with acceleration, did you fix it? my formentor has been 2 months in Cupra workshop, they already swap all the suspension with another formentor with no results,
 

TKB

Active Member
Jun 20, 2022
7
3
I have exactly the same problem, vibration starts exactly at 100 km/h, and increases with acceleration, did you fix it? my formentor has been 2 months in Cupra workshop, they already swap all the suspension with another formentor with no results,
Sorry, no. The vibration became less aparent upon tire change, but it still was there. Sold the car now.
 

tomek_olo

Cupra Leon ST VZ 2.0 245 DNPA DQ381
Jan 28, 2022
133
44
Experiencing something very similar on winter wheels. Vibration starts at ~120km/h. Balanced the wheels couple of times. Swaping them front/rear helps a bit. Is happening from the very beginning. Yesterday I've fitted the wheels for their 3rd season.

I've just booked road force balancing for Thursday thinking that maybe my tyres might be messed up. But now I see I'm not the only one.

Rims I have are Borbet, tyres Pirelli Sottozero 3.

No issues on summer OEM wheels.
 

Cvpra

Active Member
Mar 11, 2023
62
22
2022 v2 with original Bridgestone’s, 9000miles and vibrates quite badly at around 75mph+

Hoping it’s just balancing that’s the issue as at lower speed is fine.

Service due next week so asking them to look into it.
 

SRGTD

Active Member
May 26, 2014
2,683
1,532
Some VAG cars can be susceptible to vibration if the wheel bolts aren’t tightened in a star sequence - like in the picture below. Some tyre places might not do this, and they might also over-tighten the wheel bolts with an air gun rather than using a torque wrench set to the Cupra’s specified torque setting.

IMG_0599.jpeg


The bolts should initially be tightened finger tight when the wheel is still raised off the ground, then tightened a little more (but not fully torqued to the correct setting) with a socket wrench. Then lower the car to the ground and tighten to Cupra’s specified torque setting. All bolt tightening stages should be carried out in the star sequence as per the above diagram to minimise the risk of vibration.
 

tomek_olo

Cupra Leon ST VZ 2.0 245 DNPA DQ381
Jan 28, 2022
133
44
Some VAG cars can be susceptible to vibration if the wheel bolts aren’t tightened in a star sequence - like in the picture below. Some tyre places might not do this, and they might also over-tighten the wheel bolts with an air gun rather than using a torque wrench set to the Cupra’s specified torque setting.

View attachment 44828

The bolts should initially be tightened finger tight when the wheel is still raised off the ground, then tightened a little more (but not fully torqued to the correct setting) with a socket wrench. Then lower the car to the ground and tighten to Cupra’s specified torque setting. All bolt tightening stages should be carried out in the star sequence as per the above diagram to minimise the risk of vibration.
I install wheels exactly as you've described. I do it myself. Still vibrates ;)
 

SRGTD

Active Member
May 26, 2014
2,683
1,532
I install wheels exactly as you've described. I do it myself. Still vibrates ;)

What is the centre bore size of your Borbet alloys? Assuming it’s larger than the centre bore size of your OEM summer wheels which is 57.1, do you have spigot rings fitted in the centre bore of your Borbet alloys?

Although the primary purpose of spigot rings is to ensure the wheels are correctly centred on the car’s hubs, they also play a part in preventing wheel wobble / vibration. So if you don’t currently have spigot rings fitted, it might be worth getting a set of the appropriate size.
 

SRGTD

Active Member
May 26, 2014
2,683
1,532
It is not. It is exactly the same 57,1
Then the issue may be with your tyres or wheels. Could the wheels have sustained damage from poor road surfaces (e.g. potholes, sunken drain covers) in previous winters? It might be worth getting them checked for buckling if you’re getting them balanced again. How do you store your tyres? - could they have developed flat spots while in storage?
 

tomek_olo

Cupra Leon ST VZ 2.0 245 DNPA DQ381
Jan 28, 2022
133
44
Issue is happening since they were new. I went through a pothole in the first season, but ended up replacing one wheel completely - new rim and tyre.

I store them stacked on each other - lying on their side.
 

SRGTD

Active Member
May 26, 2014
2,683
1,532
@tomek_olo - So the only other thing I can think of that might be causing the vibration issue is the wheel bolts.

OEM VAG alloys use bolts with a radius / ball seat and most (but not all) aftermarket alloys use bolts with a tapered / conical seat. So if you were to use your OEM radius seat bolts on alloys designed to have tapered seat bolts, you'd have a seriously reduced contact patch between the bolts and bolt holes in the wheels, and that can lead to issues such as the creation of stress points in the alloy wheels, the bolts working loose and vibrations when driving.

So if you’re using your OEM wheel bolts, it would be worth checking whether or not these are suitable for your Borbet alloys or if they should be fitted using tapered bolts. However, if you’ve not experienced vibrations when fitting your winter wheels in previous years, wheel bolts might not be the issue.

Please update this discussion topic for the benefit of other forum members when you do establish what’s causing your vibration issue.
 
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tomek_olo

Cupra Leon ST VZ 2.0 245 DNPA DQ381
Jan 28, 2022
133
44
if you’ve not experienced vibrations when fitting your winter wheels in previous years
As mentioned - vibrations on winter wheels have been present from the beginning.

Woah, that is a really interesting hint. Ofc I use OEM bolts. Did not think about the possibility of aftermarket wheels having different seats!

I will check that for sure and let you know. It is very hard to find official info if Borbets have cone seats, but people on forums say that in 99% of situations that is the case.

I use Borbet N 7,50x18 5x112.00 ET46.00
 

pkaps

vz310
May 10, 2022
289
135
If not balancing the issue, it should be the tires, considering all rims are ok. If its a bad tire, even if it is balanced, it will still vibrate on the road.
Happened to me with Continentals few years back, my Santa Fe would still vibrate after balancing, the tire guy suspected faulty tires, the Continental guy came in and verified it. You could see when balancing ( well, I could not have seen it myself), that the tires, I think all of them or most, had a slightly uneven surface, peaks, when rolling on the balancing machine.
Continental replaced them all and no issues after that. Mind you I had purchased the tires from a the shop on a good price, they were brand new but if I remember abt a year or two old. Continental replaced them regardless and I got brand new and fresh tires.
 

tomek_olo

Cupra Leon ST VZ 2.0 245 DNPA DQ381
Jan 28, 2022
133
44
To conclude:
  • My Borbets also have ball seats for bolts - OEM bolts are OK. I have to return cone bolts that I've bought in the meantime 😅
  • I did regular balancing of all 4 wheels - service said that all 4 were out of balance.
On the newest piece of motorway near my home the vibrations are still present. But on other roads - NOT. The guy at the tyre service said that he also experienced vibrations on that road.

Case closed for now. Road is faulty, not the car. lol
 
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