Vibration 2023 4M, Cali, 15k km

[JmStockholm]

Just bought a 2023 4M, California with 15 000 km. It vibrates at 80-90 km/h, not below, and goes away around 110 km/h. Further, unaffected by rpm, gearshift or accelerating/power/freewheeling. Although the road surface influences, it's less on a super smooth roads. Suspected the wheels, but have now re-balanced one set (they where basically fine), and also driven with the winter wheels with no difference.

Also, no vibration in the steering wheel, its the whole van that's vibrating.

Any ideas or pointers on how to troubleshoot / isolate the issue?

 

[Kind of Blue]

Just bought a 2023 4M, California with 15 000 km. It vibrates at 80-90 km/h, not below, and goes away around 110 km/h. Further, unaffected by rpm, gearshift or accelerating/power/freewheeling. Although the road surface influences, it's less on a super smooth roads. Suspected the wheels, but have now re-balanced one set (they where basically fine), and also driven with the winter wheels with no difference.

Also, no vibration in the steering wheel, its the whole van that's vibrating.

Any ideas or pointers on how to troubleshoot / isolate the issue?

Why only balance one pair of wheels? Was the other pair in balance? I imagine, nay know that some better than I will ask some relevant questions and suggestions. Good fortune on this.

 

[Sasquatch]

Drive shaft or drive shaft carrier bearing. Hopefully the latter.

 

[JmStockholm]

Why only balance one pair of wheels? Was the other pair in balance? I imagine, nay know that some better than I will ask some relevant questions and suggestions. Good fortune on this.

Ah, as there were no shaking in the steering wheel I only balanced the back wheels. Nevertheless, the back wheels where fine and since changed to winter wheels with the same vibrations.

 

[JmStockholm]

Drive shaft or drive shaft carrier bearing. Hopefully the latter.

Yes, I thought about these, but the vibration doesn't vary with load, eg. accelerating hard at 80-100 km/h vs. freewheeling which I would have expected. I.e. a bigger force on the driveshaft shoud increased vibration was my guess. But, how could I check it. I guess the carrier bearing I could check for play, but the drive shaft itself? Ah, and it being a 4M I guess I need to check both front and back driveshafts.

 

[JmStockholm]

I should add It does not only appears or becomes significantly worse during acceleration, on the contrary it's unaffected by acceleration, heavy load in a hill or freewheeling down the hill, same vibration but only around 80-100 km/h not below and not above.

I should also point out that the vibrations are influenced by road condition. Some roads kind of "resonate" with the vibration in the van, while on really flat roads the vibrations gets less pronounced.

 

[Nick h]

Did you check the rear tyres?
Out of shape or unevenly worn rear tyres can manifest as the described problem on the 4M

 

[JmStockholm]

Did you check the rear tyres?
Out of shape or unevenly worn rear tyres can manifest as the described problem on the 4M

Yes, I checked the roundness and re-balanced them (they where fine though). I also have exactly the same vibrations with winter wheels as well, so I don't think it's the wheels. I actually have a third pair of all terrain wheels that are a bit unbalanced and when I put them on they, like "helped" the vibrations, and they are definitely unbalanced as with them on vibrations gets worse the faster I go, while with the two other wheels sets its smooth riding in 110 km/h.

 

[Sasquatch]

Yes, I thought about these, but the vibration doesn't vary with load, eg. accelerating hard at 80-100 km/h vs. freewheeling which I would have expected. I.e. a bigger force on the driveshaft shoud increased vibration was my guess. But, how could I check it. I guess the carrier bearing I could check for play, but the drive shaft itself? Ah, and it being a 4M I guess I need to check both front and back driveshafts.

It's liable to be the main propshaft that drives the rear diff.

The bearing likely would be easy to spot, the shaft itself not necessarily so easy and might need to come off, be stripped of UJs and properly checked for balance.

 

[JmStockholm]

It's liable to be the main propshaft that drives the rear diff.

The bearing likely would be easy to spot, the shaft itself not necessarily so easy and might need to come off, be stripped of UJs and properly checked for balance.

Yes, I guess so, will get beneath and see if I can spot balance weights missing. Also downloaded a vibration meter to the phone. Maybe the vibration frequency can provide a clue.

 

[Dundee_Kev]

The fact it's a 2023 model, let the dealer worry about it as it will be under warranty.

 

[JmStockholm]

The fact it's a 2023 model, let the dealer worry about it as it will be under warranty.

Sure, the problem is just their incompetence, and reluctance to troubleshoot and blame it e.g. on the tires or whatnot. The reapir becomes much more straightforward if I can determine what the issue is or at least be knowledgeable when discussing with them.

 

[JmStockholm]

I did 5 measured of the vibration during 20s, and there is a main frequency of 11.1 Hz. One measurement also had a spike at 28 Hz. I fed the question into Grok3, and this is it's response. Basically I need to look for something that has the wheels frequency. I hade them very professionally balanced and they where very thorough checking everything, so I still don't think it's the wheels themselves, but could be something related with the wheels in the drivetrain, Grok gives driveshafts as example. But different roads is quite strongly affecting the vibration which makes it a mystery. Anyways heres Groks answer shortened by me:

To determine the source of the vibrations you're experiencing in your VW California T6.1 at 90 km/h with a frequency of about 11 Hz, let’s analyze the possible causes step by step: unbalance in the wheels, an unbalanced drivetrain component like the propshaft, road undulations, or something loose such as engine mounts or water sloshing in the tanks. Your vehicle has 17-inch wheels with 235/65 tires, and this information will help us pinpoint the cause.

The wheel rotation frequency at 90 km/h is approximately 10.8 Hz, which is very close to the observed vibration frequency of 11 Hz. This suggests a strong possibility that the vibrations are related to the wheels.

Evaluate Drivetrain Components (e.g., Propshaft)
Next, consider the drivetrain, specifically the propshaft, as the VW California T6.1 can be front-wheel drive or 4Motion all-wheel drive (which includes a propshaft to the rear axle). If yours is all-wheel drive, the propshaft’s rotational speed depends on the transmission and differential gear ratios.

- **Differential Gear Ratio**: In most vehicles, the final drive ratio is between 3 and 4. Assuming a typical ratio of 3.5, the propshaft rotates 3.5 times faster than the wheels.
- **Propshaft Frequency**: If the wheels rotate at 10.8 Hz, the propshaft frequency would be \( 10.8 \times 3.5 = 37.8 \, \text{Hz} \). A frequency of 37.8 Hz is significantly higher than 11 Hz, so an unbalanced propshaft is unlikely to be the source.

Other drivetrain components, like driveshafts, rotate at the same speed as the wheels (10.8 Hz) in both front- and all-wheel-drive configurations, making them a possible cause.

Engine vibrations typically occur at higher frequencies. For a T6.1 (likely a 4-cylinder diesel), engine speed at 90 km/h in a higher gear might be around 1500–2000 RPM:
- **1500 RPM**: \( 1500 / 60 = 25 \, \text{Hz} \).
- **2000 RPM**: \( 2000 / 60 = 33.3 \, \text{Hz} \).

These frequencies are much higher than 11 Hz, and even harmonics or firing frequencies (e.g., 50 Hz for a 4-cylinder at 1500 RPM) don’t match. Loose engine mounts would transmit engine vibrations, but these would still be at higher frequencies, not 11 Hz.

Road undulations could induce vibrations if their spatial frequency matches the vehicle’s speed to produce 11 Hz:
- **Spatial Period**: \( \text{Speed} / \text{Frequency} = 25 / 11 \approx 2.27 \, \text{m} \).

This implies undulations spaced 2.27 meters apart, this is specific and less likely to consistently produce 11 Hz only at 90 km/h. Road-induced vibrations often excite suspension modes (e.g., wheel hop at 10–15 Hz), but the exact match with wheel rotation frequency suggests a vehicle-specific source over an external one.

- **Engine Mounts**: Loose mounts amplify engine vibrations, but as calculated, these occur at 25–33 Hz or higher, not 11 Hz.
- **Water Sloshing**: Sloshing frequencies depend on tank size and fill level but are typically low (e.g., 1 Hz or less), far below 11 Hz.

 

[Kind of Blue]

I did 5 measured of the vibration during 20s, and there is a main frequency of 11.1 Hz. One measurement also had a spike at 28 Hz. I fed the question into Grok3, and this is it's response. Basically I need to look for something that has the wheels frequency. I hade them very professionally balanced and they where very thorough checking everything, so I still don't think it's the wheels themselves, but could be something related with the wheels in the drivetrain, Grok gives driveshafts as example. But different roads is quite strongly affecting the vibration which makes it a mystery. Anyways heres Groks answer shortened by me:

To determine the source of the vibrations you're experiencing in your VW California T6.1 at 90 km/h with a frequency of about 11 Hz, let’s analyze the possible causes step by step: unbalance in the wheels, an unbalanced drivetrain component like the propshaft, road undulations, or something loose such as engine mounts or water sloshing in the tanks. Your vehicle has 17-inch wheels with 235/65 tires, and this information will help us pinpoint the cause.

The wheel rotation frequency at 90 km/h is approximately 10.8 Hz, which is very close to the observed vibration frequency of 11 Hz. This suggests a strong possibility that the vibrations are related to the wheels.

Evaluate Drivetrain Components (e.g., Propshaft)
Next, consider the drivetrain, specifically the propshaft, as the VW California T6.1 can be front-wheel drive or 4Motion all-wheel drive (which includes a propshaft to the rear axle). If yours is all-wheel drive, the propshaft’s rotational speed depends on the transmission and differential gear ratios.

- **Differential Gear Ratio**: In most vehicles, the final drive ratio is between 3 and 4. Assuming a typical ratio of 3.5, the propshaft rotates 3.5 times faster than the wheels.
- **Propshaft Frequency**: If the wheels rotate at 10.8 Hz, the propshaft frequency would be \( 10.8 \times 3.5 = 37.8 \, \text{Hz} \). A frequency of 37.8 Hz is significantly higher than 11 Hz, so an unbalanced propshaft is unlikely to be the source.

Other drivetrain components, like driveshafts, rotate at the same speed as the wheels (10.8 Hz) in both front- and all-wheel-drive configurations, making them a possible cause.

Engine vibrations typically occur at higher frequencies. For a T6.1 (likely a 4-cylinder diesel), engine speed at 90 km/h in a higher gear might be around 1500–2000 RPM:
- **1500 RPM**: \( 1500 / 60 = 25 \, \text{Hz} \).
- **2000 RPM**: \( 2000 / 60 = 33.3 \, \text{Hz} \).

These frequencies are much higher than 11 Hz, and even harmonics or firing frequencies (e.g., 50 Hz for a 4-cylinder at 1500 RPM) don’t match. Loose engine mounts would transmit engine vibrations, but these would still be at higher frequencies, not 11 Hz.

Road undulations could induce vibrations if their spatial frequency matches the vehicle’s speed to produce 11 Hz:
- **Spatial Period**: \( \text{Speed} / \text{Frequency} = 25 / 11 \approx 2.27 \, \text{m} \).

This implies undulations spaced 2.27 meters apart, this is specific and less likely to consistently produce 11 Hz only at 90 km/h. Road-induced vibrations often excite suspension modes (e.g., wheel hop at 10–15 Hz), but the exact match with wheel rotation frequency suggests a vehicle-specific source over an external one.

- **Engine Mounts**: Loose mounts amplify engine vibrations, but as calculated, these occur at 25–33 Hz or higher, not 11 Hz.
- **Water Sloshing**: Sloshing frequencies depend on tank size and fill level but are typically low (e.g., 1 Hz or less), far below 11 Hz.

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I assume that you are using the correct tyre pressure for the particular tyre that you are using.

 

[JmStockholm]

Grok produced this suggestions for instructions to the shop:

**Summary for Repair Shop: Vibration Diagnosis for VW California T6.1 4Motion**

**Vehicle Details**:
- Model: VW California T6.1 4Motion (all-wheel drive), 2023 model
- Mileage: 22,000 km
- Wheels/Tires: 17-inch rims with 235/65 R17 tires, professionally balanced by a reputable shop

**Issue**:
- Vibrations occur at 90 km/h (~100 km/h range), with a frequency of approximately 11 Hz.
- Vibrations are significantly influenced by road conditions:
- Stronger on roads with longitudinal undulations, even if smooth and in good condition.
- Much weaker or nearly absent on flat, smooth roads without undulations.

**Analysis Provided**:
- Wheel rotation frequency at 90 km/h is ~10.8 Hz, closely matching the observed 11 Hz vibration.
- Wheels were ruled out as the source due to recent professional balancing.
- Vehicle’s low mileage (22,000 km on a 2023 model) makes worn suspension components (e.g., shocks, bushings) less likely.
- Drivetrain components considered:
- **Driveshafts**: Rotate at ~10.8 Hz, aligning with the vibration frequency. A minor manufacturing defect, imbalance, or CV joint issue could cause vibrations, with longitudinal undulations exciting the drivetrain.
- **Propshaft**: Rotates at ~37.8 Hz (assuming a 3.5:1 final drive ratio), less likely due to frequency mismatch, though a fault (e.g., universal joint) could contribute indirectly.
- **Engine**: Operates at 25–33 Hz (1500–2000 RPM), not a match for 11 Hz.
- Longitudinal undulations (e.g., ~2.27 m spacing at 25 m/s for 11 Hz) suggest a road-induced excitation tied to wheel speed, possibly interacting with the 4Motion drivetrain rather than suspension wear.
- Other possibilities (e.g., loose mounts, exhaust) are unlikely due to frequency mismatch and the vehicle’s new condition.

**Conclusion**:
- Most likely source: **Driveshaft issue** (e.g., minor imbalance, CV joint defect, or misalignment), triggered or amplified by longitudinal road undulations in the 4Motion system.
- Secondary consideration: Propshaft or drivetrain resonance, though less probable given the frequency.
- Suspension wear is improbable due to the vehicle’s age and mileage.

**Recommended Actions**:
1. **Inspect Driveshafts**: Check front and rear driveshafts, particularly CV joints, for manufacturing defects, slight imbalance, or early wear, even with low mileage.
2. **Examine Propshaft**: Inspect for alignment or joint issues as a secondary check, given the 4Motion system.
3. **Road Test**: Replicate conditions (90–100 km/h on a road with longitudinal undulations) to verify the source and confirm the fix.
4. **Optional Suspension Check**: If drivetrain checks are inconclusive, briefly inspect suspension response to undulations, though wear is unlikely.

**Notes**:
- The 11 Hz vibration ties to wheel/driveshaft speed (10.8 Hz), and longitudinal undulations (not general roughness) are the key trigger. Focus on drivetrain components, leveraging the vehicle’s near-new status and confirmed wheel balance.

 

[JmStockholm]

I assume that you are using the correct tyre pressure for the particular tyre that you are using.

Yes, the tire shop checked that, but I could experiment with filling them up with e.g. 15% more just to test it out.

 

[Kind of Blue]

I also wonder if particular tyre, its design manufacturer etc might be more inclined to sympathetic resonance at certain speed with certain road topography. Varying the pressure may possibly change the speed of interaction or force. Some tyre types etc may damp out resonance more than others. Ii have little knowledge of Swedish road construction.

 

[DaveD]

Grok produced this suggestions for instructions to the shop:

**Summary for Repair Shop: Vibration Diagnosis for VW California T6.1 4Motion**

**Vehicle Details**:
- Model: VW California T6.1 4Motion (all-wheel drive), 2023 model
- Mileage: 22,000 km
- Wheels/Tires: 17-inch rims with 235/65 R17 tires, professionally balanced by a reputable shop

**Issue**:
- Vibrations occur at 90 km/h (~100 km/h range), with a frequency of approximately 11 Hz.
- Vibrations are significantly influenced by road conditions:
- Stronger on roads with longitudinal undulations, even if smooth and in good condition.
- Much weaker or nearly absent on flat, smooth roads without undulations.

**Analysis Provided**:
- Wheel rotation frequency at 90 km/h is ~10.8 Hz, closely matching the observed 11 Hz vibration.
- Wheels were ruled out as the source due to recent professional balancing.
- Vehicle’s low mileage (22,000 km on a 2023 model) makes worn suspension components (e.g., shocks, bushings) less likely.
- Drivetrain components considered:
- **Driveshafts**: Rotate at ~10.8 Hz, aligning with the vibration frequency. A minor manufacturing defect, imbalance, or CV joint issue could cause vibrations, with longitudinal undulations exciting the drivetrain.
- **Propshaft**: Rotates at ~37.8 Hz (assuming a 3.5:1 final drive ratio), less likely due to frequency mismatch, though a fault (e.g., universal joint) could contribute indirectly.
- **Engine**: Operates at 25–33 Hz (1500–2000 RPM), not a match for 11 Hz.
- Longitudinal undulations (e.g., ~2.27 m spacing at 25 m/s for 11 Hz) suggest a road-induced excitation tied to wheel speed, possibly interacting with the 4Motion drivetrain rather than suspension wear.
- Other possibilities (e.g., loose mounts, exhaust) are unlikely due to frequency mismatch and the vehicle’s new condition.

**Conclusion**:
- Most likely source: **Driveshaft issue** (e.g., minor imbalance, CV joint defect, or misalignment), triggered or amplified by longitudinal road undulations in the 4Motion system.
- Secondary consideration: Propshaft or drivetrain resonance, though less probable given the frequency.
- Suspension wear is improbable due to the vehicle’s age and mileage.

**Recommended Actions**:
1. **Inspect Driveshafts**: Check front and rear driveshafts, particularly CV joints, for manufacturing defects, slight imbalance, or early wear, even with low mileage.
2. **Examine Propshaft**: Inspect for alignment or joint issues as a secondary check, given the 4Motion system.
3. **Road Test**: Replicate conditions (90–100 km/h on a road with longitudinal undulations) to verify the source and confirm the fix.
4. **Optional Suspension Check**: If drivetrain checks are inconclusive, briefly inspect suspension response to undulations, though wear is unlikely.

**Notes**:
- The 11 Hz vibration ties to wheel/driveshaft speed (10.8 Hz), and longitudinal undulations (not general roughness) are the key trigger. Focus on drivetrain components, leveraging the vehicle’s near-new status and confirmed wheel balance.

Is it possible to mount a go-pro camera underneath the van with a view of the prop shaft?
Take a short video while you drive in a manner that causes the vibration.
I wonder if it would show the shaft vibrating?
Maybe it is possible to do the same for each drive shaft?

 

[Kind of Blue]

Just a thought, a road near to where I live causes a deep rumbling sound exceedingly noisy inside the vehicle, very deep ow herz in tone. On examining the road surface I could tell that an very large excavator with tracks had travelled some distance from the beginning of the road. I know that a very large excavator had been used to excavate an escarpment on a local farm. No other road surface has ever caused that type of visceral excitement in any vehicle that I have ever driven. Probably not the same as yours but I thought that I would mention it.

 

[phazer]

Have you had the alignment checked? When I lowered mine (more) the tyres were making a lot of noise as the wheels on the rear were effectively pointing out wards like \--/ once alignment was done they're back to super quiet.