2015 Passat TDI - Vibration at 120ish KM/H (74mph)

[mrrhtuner]

Hello everyone, I've had my 2015 Passat TDI for about 1.5 years now and I drive roughtly 100km (62miles) round trip each day for work.
I am the second owner and purchased the car from the original owner with 82,000km on the odometer.

When I purchased the car, it was December 2022 and the car was on winters. The drives to work and back home were fine. The suspension feels good and the alignment tested fine.

When I installed the OEM 19" VW Luxor wheels and started the drives in the spring, I noticed a slight wheel vibration at about 120km. The vibration happens more when you accelerate but if you let off, you can still feel it. I don't feel the vibration really under 120km but it does feel the same at 120-140ish.

I have taken the car to check the alignment and it was adjusted but it didn't fix the issue. This spring, I had taken all 4 wheels to our local performance tire shop to have the wheels checked for balance, everything was fine.

It was noticed that out of the 4 tires, one was much newer.

Now, I do recall the previous owner mentioning to me that his wife hit something and caused damage to the tire and the tire was replaced. I don't have a gauge to measure tire wear but 1 tire out of the 4 looks nearly new while the other 3 look to be up for replacement next year.

That is my only issue with the drivability of the car, everything else in terms of suspension/steering seems fine and tire wear is even.

What I am unsure about is that with my winters, the car is smooth all the way to 150km/h. No complaints at all. But I am unsure if that is due to the thickness of the winter tire and allowing for possibly more absorption? I am not sure if that makes sense.

But so far:

• Alignment checked, adjusted and good
• Tires are all balanced

If I had a suspension issue, I would imagine that I should feel it my winter tires also, especially at higher speeds, which I don't.
I'm considering buying all 4 new tires since they eventually have to be replaced but from my experiences before, throwing money at issues is not always a solution.

Any suggestions on how to approach this issue? has anybody dealt with anything similar in the past?


Thank you

 

[Johhny04]

I would lean towards balance of tires. Even though the tire shop balanced them, their machine could be out. I've had this happen to me before. One shop balanced my wheels but at over 105 km/h I would feel a vibration. I went to another shop and had them rebalance. Vibration gone. If they are not keeping up with maintenance of their machines, or the person balancing the wheel isn't being doing it precisely, it'll result in a bad balance.

 

[mrrhtuner]

I would lean towards balance of tires. Even though the tire shop balanced them, their machine could be out. I've had this happen to me before. One shop balanced my wheels but at over 105 km/h I would feel a vibration. I went to another shop and had them rebalance. Vibration gone. If they are not keeping up with maintenance of their machines, or the person balancing the wheel isn't being doing it precisely, it'll result in a bad balance.

Thanks,
The only reason I do believe the tire shop is that they only deal with rims/tires (not a typical mechanic shop) and they often have very high quality cars (Porsche, Mercedes, Ferrari). I've known the owners since the business was started so I do have trust in their tools as their reputation speaks highly of their quality of work.

I do agree, I was hoping the re-inspection of the rims would have fixed the issue. They re-balanced one or two wheels but that didn't help.

 

[JELLOWSUBMARINE]

Swap the wheels out 1 at a time with the knownn good set. See wĥat happens on the problem speed

 

[pedroYUL]

Check this control arm bushing for tears:

 

[oilhammer]

The NMS is hard on compliance bushings (pictured above). And if you have wheels over 16" rim size, they are easily bent. So easily, I'd not be surprised at all if more than one are bent. You can balance a tire on a bent wheel until the cows come home, it's still bent, still not round, and on big rim low profile wheel/tires, you're going to feel it.

The newer DSG cars are also hard on drive axles, not really sure why. If it is the increase in power such that it is easily felt, or something in VAG's axle supplier changed, who really knows. But I know I have replaced more DSG axles on these cars that I did on any previous generations. Raxles is a good go-to if you cannot source new GKNs (the Chinese ones from the parts store are garbage, don't even bother).

The alignment won't cause that type of complaint. If the vibration changes a lot with load, it is usually the drive axle or the suspension shifting (again, those bushings). Usually wheel/tire balance/trueness will be speed related.

 

[NSTDI]

First do the recommended wheel switch one at a time using your winters, see if vibration goes away. I’ve had more bad tire balancers than good ones.
If it is a tire or rim and you have confidence in your tire balancer, have them check the balance at the speed you have the problem.

 

[oilhammer]

Balancers don't spin the wheels that fast, LOL.... this isn't NASCAR.

 

[ZippyNH]

Stupid question....
Aftermarket rims?
Have seen when the hub centering parts are missing or the wrong size a similar feel....