Terios Shudder/Vibration

[TeriTheTerrible]

We have an '09 Terios 4x4 which we have owned and loved for several years now.
It has been rock-solid and given us almost no hassles at all - until recently. But we don't believe it has anything to do with the vehicle, but rather with poor workmanship or technical ineptitude.

Here's the story:
After taking it for a service, my wife noticed heavy vibration coming from the front left wheel so we returned it to the workshop.
The technician noted worn wheel bearings and replaced them.
After replacing the wheel bearings, technician noted there was still a "slight vibration" at just over 110km/h.
Fast forward a bit and we were told the vehicle is ready collect - with a hefty invoice.
When queried, the workshop had to send the vehicle for "prop shaft repairs".
We spoke with the technician, who told us that they noticed the prop shaft boot had perished and cracked and, as a result of the grease escaping, there was play on the universal joint which had to be replaced.
They sent the vehicle off to a prop shaft specialist who cut off the OEM universal joint and replaced it with a generic one (without customer consent ).
After driving the vehicle, we noted a shudder/vibration from 80km/h upwards, but only when power is coming through the drivetrain ie: shudder is present at 110km/h but disappears when you lift off the accelerator. This tells me it has nothing to do with wheels/shocks but rather with the drivetrain.
We returned the vehicle to the workshop who, in turn, returned it to the prop shaft specialist who re-checked their work and found no fault. However, the issue persists.

The technician suspects an issue with the gearbox but won't know unless the gearbox is stripped and inspected - at our expense.
This issue was not observed after the wheel bearings were replaced when there was "slight vibration over 110km/h" - before the prop shaft modifications.
I'm a software developer with a basic knowledge of vehicles, but my gut tells me it has very little to do with the gearbox and more to do with the (unsolicited) prop shaft modifications.

Any experts out there willing to comment?

[Schambies]

We have an '09 Terios 4x4 which we have owned and loved for several years now.
It has been rock-solid and given us almost no hassles at all - until recently. But we don't believe it has anything to do with the vehicle, but rather with poor workmanship or technical ineptitude.

Here's the story:
After taking it for a service, my wife noticed heavy vibration coming from the front left wheel so we returned it to the workshop.
The technician noted worn wheel bearings and replaced them.
After replacing the wheel bearings, technician noted there was still a "slight vibration" at just over 110km/h.
Fast forward a bit and we were told the vehicle is ready collect - with a hefty invoice.
When queried, the workshop had to send the vehicle for "prop shaft repairs".
We spoke with the technician, who told us that they noticed the prop shaft boot had perished and cracked and, as a result of the grease escaping, there was play on the universal joint which had to be replaced.
They sent the vehicle off to a prop shaft specialist who cut off the OEM universal joint and replaced it with a generic one (without customer consent ).
After driving the vehicle, we noted a shudder/vibration from 80km/h upwards, but only when power is coming through the drivetrain ie: shudder is present at 110km/h but disappears when you lift off the accelerator. This tells me it has nothing to do with wheels/shocks but rather with the drivetrain.
We returned the vehicle to the workshop who, in turn, returned it to the prop shaft specialist who re-checked their work and found no fault. However, the issue persists.

The technician suspects an issue with the gearbox but won't know unless the gearbox is stripped and inspected - at our expense.
This issue was not observed after the wheel bearings were replaced when there was "slight vibration over 110km/h" - before the prop shaft modifications.
I'm a software developer with a basic knowledge of vehicles, but my gut tells me it has very little to do with the gearbox and more to do with the (unsolicited) prop shaft modifications.

Any experts out there willing to comment?

I suspect you might be right, but I would also rule out tyre balancing and engine mounts. As far as I understand the propshaft would be spinning whether you are depressing the accelerator or not, as it would be driven through the diff; or in case of the front shaft through the gearbox directly. So at speed, with or without accelerator input, the driveshaft would be affected. That applies to tyre balancing as well. Check whether engine RPM while immobile causes similar vibrations as well.

If that is ruled out then take it to another propshaft specialist and have it balanced again. It could just be that.

[TeriTheTerrible]

I suspect you might be right, but I would also rule out tyre balancing and engine mounts. As far as I understand the propshaft would be spinning whether you are depressing the accelerator or not, as it would be driven through the diff; or in case of the front shaft through the gearbox directly. So at speed, with or without accelerator input, the driveshaft would be affected. That applies to tyre balancing as well. Check whether engine RPM while immobile causes similar vibrations as well.

If that is ruled out then take it to another propshaft specialist and have it balanced again. It could just be that.

Hey Schambies - thanks for the reply!

I did not test engine RPM while immobile, but did test while travelling at approx 110km/h by taking the vehicle out of gear and taking the engine up to through the normal rev range. No vibration noted during this test.
The vibration is definitely more pronounced under engine load, so this makes me (even more) suspicious of drivetrain.

[Commander]

I don't know the Terrios specifically, but what I suspect could be an issue is if the propshaft carrier bearing is unwell, the propshaft does spin as long as the wheels are spinning, but it behaves differently under load than when coasting. I don't know the Terrios's layout or components, so it could be something else, but I doubt it would be gearbox. It is also strange that all this started out of the blue... It may be worth while removing the propshaft and taking the car for a drive to see if the variation stays. Perhaps someone that knows the drivetrain a bit better can comment?

[TeriTheTerrible]

I don't know the Terrios specifically, but what I suspect could be an issue is if the propshaft carrier bearing is unwell, the propshaft does spin as long as the wheels are spinning, but it behaves differently under load than when coasting. I don't know the Terrios's layout or components, so it could be something else, but I doubt it would be gearbox. It is also strange that all this started out of the blue... It may be worth while removing the propshaft and taking the car for a drive to see if the variation stays. Perhaps someone that knows the drivetrain a bit better can comment?

Thanks, Commander! After doing a bit of research, it seems a bad carrier/centre bearing does fit the "vibration under acceleration" symptom.

[Commander]

Thanks, Commander! After doing a bit of research, it seems a bad carrier/centre bearing does fit the "vibration under acceleration" symptom.

Have a look on the Toaureg groups, it is a common problem on them and there is a cheap and easy DIY "bush fix" for it using cable ties and coolant hose, this may also work on the Terrios. Usually it is the rubber "bushing" that fails and not the bearing it self. Most people who try to replace the carrier bearing have balance issues afterward, so this is a good way of fixing it for not a lot of money and with less risk. The fix lasts years, so don't be worried that it is only a short term solution. DUe to the difficulty in balancing, changing the bearing only often leads to having to replace the whole prop shaft which can be pricey.