What revs does the vibration occur and in which gears ?
Does the vibration occur when the engine is reved in neutral ?
Have the engine mounts been checked for tightness ?
Are the springs/shockers ok ?
Has the cambelt been changed ?
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Hi - The vibration is most noticable in 6th and at around 2000-2500 revs. If you increase speed to 75-80mph vibration becomes worse. It continues as you decelerate and then calms down again as you get back to 70 or just below. There is no sign of it at lower speeds or other gears. I don't think it happens in neutral but I will check. Apparently there are no obvious signs of wear in steering, springs or shockers. This modal has a camchain.
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Hi - there is a very slight vibration through the steering column. Some comes through the seats. If you look at the bonnet that seems to be vibrating the most.
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Still sounds like a wheel balance problem to me - or a defective tyre.
Edited by Peter.N. on 15/07/2008 at 12:05
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Still sounds like a wheel balance problem to me - or a defective tyre. Yes I hope so - I can't fine anyone else with a similar problem and I have looked on loads of forums. Garage have suggested it might be a drive shaft issue/alignment
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does it make any difference if you're in fifth or sixth gear?
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does it make any difference if you're in fifth or sixth gear? well it always appears to be worse in 6th because it only happens above 70mph. In 5th gear its still there but not so severe.
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This could be a worn dual mass flywheel problem. Certain combinations of forces and frequencies can cause the flywheel to resonate and cause vibration. Do you get any noises or rumbles when switching the engine off or hot starting with the clutch up?
If the extent of the vibration differs depending on which gear you're in it's unlikely to be a driveshaft problem because the shaft will be spinning at the same speed regardless.
Does the vibration pass at all? Eg. does it fade as you go faster than 70mph? It is worse when crusing or accelerating?
Try the following (in a suitable location, obviously):
Induce the vibration and drop to 4th gear - does it reduce or disappear?
Induce the vibration and dip the clutch - any changes?
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Thank you Quinney100. The vibration does not pass or fade - my garage road tested up to 100mph and it was still apparent. It only fades when you drop back below 70mph. It seems worse when cruising. I do have a low vibration at idle but the garage says it's the belt tensioner and not (yet) anything to worry about. That vibration disappears as soon as you put on a few more revs. Are they wrong about this?
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The aux belt vibration is a common problem and disappears with a slight touch of the throttle. I had mine done under warranty - they replaced the belt, tensioner and the idler roller which I guess would be quite expensive if you were paying. I'd agree with the garage that it is more of an annoyance than anything to worry about - the drumming noise irritated me more than the vibration.
Nailing the problem down to the flywheel is going to be quite difficult and due to the cost involved I would make sure it's definitely not a wheel or tyre problem first. If you don't have a full size spare I'd get hold of one (ebay?) and swap each of the wheels out in turn. It could be a buckled wheel or a flatspotted or out-of-round tyre which may not show up on a wheel balancer. You could also swap the wheels front to back to see if that makes any difference.
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I think you are talking sense re the have another go at wheel balancing/buckled wheel first Quinney100. The garage did swap the front and backs after a recent sevice and post that the vibration was a lot, lot worse. But beause they said they had rebalanced everything again we started looking for more serious problems. Thing is though the garage never noticed any poor tyres or wheels in all this re-balancing. I think I'm going to go and try a Tyre centre and swap back the wheels to see what happens. What and where is a dual mass flywheel?
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I wonder at what roadspeed the wheels are balanced at. Can these machines spin the wheels the equivelent of 70 mph?
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Apparently that's not how wheel balancing works. It's all done via a kind of mean revolution speed and then calibrated with software of some kind.
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>>I wonder at what roadspeed the wheels are balanced at.
It doesn't matter. Seriously!
What does matter is the difference between the signal from the machine's sensors, and the amount of spurious noise measured by the sensors. So, hand spun wheel balancers can, and do, give excellent results, because there's no vibration from the motor and transmission interfering with the signal.
The other thing is that imbalance is not speed dependnet at all! By that, I mean that the imbalance itself is caused by an uneven distribution of mass, there's nothing to do with speed there.
What is speed dependent is;
a) The amount of force (or moment for dynamic imbalance) produced by a rotating wheel is proportional to speed squared.
b) In the vehicle, you tend to only feel the imbalance when it excites a resonance of either the suspension, or steering.
Point a) means that spinning the wheel faster will give more output from the machine's sensors, but, in general, the sources of vibration and noise in a machine will also increase in the same way - you don't, necesarily, gain by balancing with a quickly spinning wheel.
So, a wheel that is truly and properly balanced at whatever speed on a machine can be run at varying speed on a car, and be OK.
A wheel that is not properly balanced will have some speeds - on the car - where the imbalance is felt by the occupants.
For the OP.
If you want to make sure it isn't the flywheel, while the car is vibrating, put the clutch down, and allow the engine to return to tick over. Does the vibration stop?
Another way, is that if the vibration happens at 70mph, is it the same at 70 in 3rd, at 70 in 4th, at 70 in 5th, and at 70 in 6th?
One thing that people who work in tyre fitting very rarely seem to do is to checkthe wheels really carefully for damage and lateral runout , and radial runout. For the runouts, with alloy wheels, I would be hoping to see figures less than about 0.5mm.
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If you are anywhere near Hull Tyremen on Anlaby Road do on-car wheel balancing.
Had a similar problem with a Merc V-Class, it turned out to be buckled front wheels (from new)
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thanks but I live in Hertfordshire!
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There's a company called Vibration Free in Bicester (not too far for you to get to) www.vibrationfree.co.uk - they're experts at balancing anything on cars that spins.
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It could be the intermediate drive shaft bearing. The intermediate shaft connects the diff to the right hand draive shaft.
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If it is the wheels being unbalanced then try using a different garage to check the balance just in case the wheel balance machine is out of sync.
I once had some new front tyres fitted by a well known chain and the front wheels vibrated afterwards from around 60 mph, so I took the car back and they checked and their machine said they were ok. So I took the car to another garage and they checked and found they were not balanced, they corrected the balance and all was well. The original garage wheel balance machine needed recalibrating and was giving out incorrect information.
Edited by MikeTorque on 16/07/2008 at 00:45
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TO EVERYONE: Thanks for all your advice and help. I'm going to take the car to another wheel balancing/tyre centre place and have them really carefully(if that's possible) check wheels and tyres. I hope it improves the condition. By the way, the vibration does NOT dissappear when you dip the clutch at 75-80mph and let revs return to idle. That means it's more likely to be a balancing issue - doesn't it?
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>>That means it's more likely to be a balancing issue - doesn't it?
Well, you've ruled out the expensive dual mass flywheel!, and so, the vibration must be from something that's still spinning at speed, i.e., the wheels and driveshafts.
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have you had your tyres balanced, checked? It certainly won't be the flywheel
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thanks - did talk to them but cost means I'll try other things first.
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I'd swap the wheels front to back to see if this changes the problem, that will tell you if its the wheels or a hub / driveshaft issue.
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Tracking ought to be checked too, and suspension and steering joints, and possible uneven tyre wear resulting from incorrect tracking. Even a dodgy front damper can cause vibration I have seen it asserted.
Sometimes a severely out-of-balance rear wheel can make a car vibrate at speed too. Always make sure they are all balanced unless you never go fast.
I have also experienced imbalance resulting from a single, heavy security nut on each of the front wheels. Puzzled me and a tyre place in Kendal for hours. Doh!
Edited by Lud on 16/07/2008 at 19:46
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Tracking ought to be checked too and suspension and steering joints and possible uneven tyre
EVERYONE - I will report back on this thread as soon as I have had another go at the balancing issues. It will probably be next week. If anyone has anymore useful ideas please do post them. I will continue to check this thread.
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Hi, Did you eventually get to the bottom of the problem. My car is the same car same year with the same mileage and I cannot find the source of the vibration
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