Hi gang I'm hoping somebody can help try & advise of the following.
When you are accelerating the Doblo it's fine till 40mph then a real shake comes through the car until around 50mph. It's just gone through a compliance test for Hackney carriage so it's nothing the eye can see or is checked on a MOT. We've checked tyres & changed them around, a mechanic doesn't think it's the drive shafts after looking at them whilst on a ramp running, he does think 80% it's a seised fly wheel but can't be 100% sure. With a bill looming of around £800-£1000 I thought I'd throw it out to see if anyone else as suffered this problem. Thank you for your time. Andy.

So is this a fault nobody else has experienced? Or do I need to do something to get a response?

Hi,

I don't think you're being ignored, I suspect nobody has anything to suggest at the moment.

Just thought of something.

Does the vibration occur at the same road speed in different gears?

Sorry Niall I didn't mean to sound funny, wasn't sure if my post couldn't be replied too but now I know it can, thank you. Yes it does vibrate at around 46 mph in all gears, but dip the clutch & it runs smooth.

abigtoll said:

Sorry Niall I didn't mean to sound funny, wasn't sure if my post couldn't be replied too but now I know it can, thank you. Yes it does vibrate at around 46 mph in all gears, but dip the clutch & it runs smooth.

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I'm no expert but my logic goes:

Vibration happens at different engine speeds but at the same road speed.

Therefore unlikley to be something that turns at engine speed so not going to be the clutch or DM flywheel (if it has one).

I'd get back under the car and grab the diff end of the drive shafts and give them a good wiggle. I'd be looking for movement in the bearings on the output of the diff. When under load they may allow a slight twist hence the vibration, when coasting everything goes back to where it should and the vibration stops.

As I say, it's only a theory and it may shortly get shot down but some real experts.

abigtoll said:

a mechanic doesn't think it's the drive shafts after looking at them whilst on a ramp running,.

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I'm amazed he can tell just by looking, this is a fairly exact science.

Many years ago I had a similar problem & the 'fix' was to have the tyres balanced on the car.
Interestingly, I've not seen the tech used since but iirc, the mech lifted the front wheels clear of the ground then rolled a small sit-on device up to the wheel. A tyre on the device made contact with the car tyre & spun it.
My problem wasn't the wheel as this had already been 'properly' balanced, it was somewhere in the drive train.
Looking back, it may have been something as simple as the jubilee clip holding the new CV boot (the extra weight from the worm drive) - who knows?
Google throws up http://vibrationfree.co.uk/ (just outside Bicester)

I had a very similar issue on my old Berlingo which turned out to be the rear tyres. Although the car had done a high mileage the rear tyres were not worn down but when you spun them on a ramp you could see that they were mis-shapen (side to side movement when viewed from the back). New back tyres sorted it for me.

HTH

Peter

I wouldn't rule out a misshapen or stepped tyre either. Also check for a bent wheel. If its a wheel balance issue it does also tend to happen at about that speed, but the shaking can stop at higher speeds, so again this is a possibility.

While its not impossible to be a flywheel issue there are many cheaper things to check first.

reminds me I must balance the wheels this week as one of my doblos (dobli) does this at around 50mph

abigtoll said:

Hi gang I'm hoping somebody can help try & advise of the following.
When you are accelerating the Doblo it's fine till 40mph then a real shake comes through the car until around 50mph. It's just gone through a compliance test for Hackney carriage so it's nothing the eye can see or is checked on a MOT. We've checked tyres & changed them around, a mechanic doesn't think it's the drive shafts after looking at them whilst on a ramp running, he does think 80% it's a seised fly wheel but can't be 100% sure. With a bill looming of around £800-£1000 I thought I'd throw it out to see if anyone else as suffered this problem. Thank you for your time. Andy.

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hi i had the same problem not on a doblo but the same symptoms you describe!

and it was the roller bearings on the end of the driveshaft that 1 had collapsed, put new roller bearings on and problem solved! the driveshaft has a knuckle with 3 roller bearings running at speed on 2 means it is out of balance hence the vibration,

as has been mentioned above you cant tell just by looking at the driveshaft!

Yes it does vibrate at around 46 mph in all gears, but dip the clutch & it runs smooth.

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That is exactly the same problem as i had and it was the drivers side driveshaft bearings going into the gearbox!

here is a pic of the bearings am talking about, in the bearings there are little pins these fall out meaning the bearing is failing!
[ame="http://www.google.co.uk/search?hl=en&tbm=isch&tbs=simg:CAQSYgmBf7wb3nLS3BpOCxCwjKcIGjwKOggBEhTZBt0G2AbWBt4H3wfuB-0H4gfhBxog-CSsiPqIFkWGDcZViNPVnq_1Ukzs3-d9Cvje0e6UHKioMCxCOrv4IGgAMIQHaug1Yy6ic&sa=X&ei=xiw9Ue6kL6PB7Ab7jIGQDQ&ved=0CCkQwg4&biw=1024&bih=629&q=driveshaft%20bearings"]driveshaft bearings - Google Search[/ame]

as you can see there is 3 and the car will still drive on 2 its only at speed will you notice as you did with the vibration!

Is the shake through the wheel or the car, check balance on all four wheels

Hello,

any updates on the subject?

I had exactly this problem earlier this year. After chucking a few quid (new drop links & ARB bushes) at the back end I spent some time on google & a common theme of tyres came up.
As luck would have it, someone was selling a brand new pair of similarly sized tyres on Facebook marketplace. £60 the pair, fitted, balanced on my driveway, on my lunchbreak. On my way back to work, I took a slightly longer route where I could put my foot down - instant sweetness :slayer: