Technical Shaking at 40 - 50 mph

[Rogerg110]

Hello, I have a problem with my Ducato based 2013 Motorhome. When accelerating through 40-50mph the van shakes proportionally to how hard I accelerate, eg up hill the shaking is worse. Driving at a constant speed between these limits no shaking! I have been told it could be a drive shaft problem, but which one? All the wheels have been balanced.
Any ideas as I am in the south of France on tour so not easy to get diagnosis

 

[spidermania]

Driving at a constant speed between these limits no shaking! I have been told it could be a drive shaft problem

Check the simple things first before you spend an arm and a leg.

1. Lug nuts, are they all on and if so tighten
2. Tire balance is off
3. Wheel alighment is off.

And finally before the driveshaft, could even be wheel bearings.

Don't panic, the FIAT FORUM has top people here that can help you.

 

[airwave]

40-50mph the van shakes

Simple question , have you had a new tyre fitted , before this all kicked off ?

 

[lancepar]

Simple question , have you had a new tyre fitted , before this all kicked off ?

Or, have you tried the rear wheels on the front.
Not the same issue as yours.
The front tyres had worn unevenly causing the our MoHo to pull to one side underway and pulling to one side when stopping.
Garage tried all sorts of checks on the front end before swapping wheels, The tyres looked fine but weren't.
Tyres were replaced.

 

[Rogerg110]

Or, have you tried the rear wheels on the front.
Not the same issue as yours.
The front tyres had worn unevenly causing the our MoHo to pull to one side underway and pulling to one side when stopping.
Garage tried all sorts of checks on the front end before swapping wheels, The tyres looked fine but weren't.
Tyres were replaced.

Have only recently bought the MH and had all the wheel balances checked but not sure if uneven tyre would show up? . Also had new tyres fitted to the front.
Also the problem is much worse with hard acceleration! We are in Spain just to make things more complicated!

 

[bugsymike]

Have only recently bought the MH and had all the wheel balances checked but not sure if uneven tyre would show up? . Also had new tyres fitted to the front.
Also the problem is much worse with hard acceleration! We are in Spain just to make things more complicated!

Can be a faulty drive shaft or if a CV joint or boot has been replaced recently and a needle bearing etc . dislodged inside drive shaft joint.
Ideally this is done on a ramp safely in a garage, but if you feel like taking your life in your hand, try this!!!

Jack and support each front wheel individually (note it must be supported on the suspension towards the outer end so that the road wheel is at it's normal position as if on the road, but the support must be safely away from the moving wheel) then if someone carefully puts vehicle in gear and at half the road speed it normally wobbles at, due to differential gear action as you are only running one wheel at a time to test and see which side is worse. Note the reason for above detail is if problem happens at 50mph on the speedo with only one wheel in the air that wheel could be doing 100mph!!! So if it falls off the supports
See if that side vibrates/wobbles etc. Then repeat operation with the other side.
I have done this many times to locate an issue whilst working in the motor trade, but it must be done safely, so if it can be done in the manner I suggest, but on a garage ramp (not a wheel free type) so much the better.
The reason not to just "wheel free it" or jack vehicle up on the chassis is this causes the suspension to hang down , meaning the drive shafts are out of normal running position and may wobble anyway.
Of course another thing to check is if any engine mountings including gearbox supports are worn or broken encouraging engine and gearbox to move when under load, up hill etc.
Eccentric tyres can cause the issue , but you have already eliminated that.
Unlikely but if it was on a ferry and lashed down over the driveshafts that can/will cause damage also.
If only bought recently then quite possible seller was aware of the problem!!!

 

[Rogerg110]

Thank you for your response.
As it happens the drives haft boots were replaced last year. When I got home from buying the van in August the jubilee clip holding the boot at the wheel end was missing. Had it replaced with grease so could be a problem with the needle bearing. Hoping get back to UK for the fix! Does not seem to have got worse in the last 1500 miles.

 

[bugsymike]

Thank you for your response.
As it happens the drives haft boots were replaced last year. When I got home from buying the van in August the jubilee clip holding the boot at the wheel end was missing. Had it replaced with grease so could be a problem with the needle bearing. Hoping get back to UK for the fix! Does not seem to have got worse in the last 1500 miles.

Does seem a likely place to start with, I have come across it several times over the years.
Hopefully just one side.

 

[Rogerg110]

Thank you I will look into it when I get home, hopefully!

 

[airwave]

Have only recently bought the MH and had all the wheel balances checked but not sure if uneven tyre would show up? . Also had new tyres fitted to the front.
Also the problem is much worse with hard acceleration! We are in Spain just to make things more complicated!

Hmmm , you say you had the wheels re-balance , was that by the same company who fitted them , take it somewhere else ! . Eliminate the simple first .

We had a similar problem on heavy trucks many years back , which turned out to be a tyre incorrectly fitted . Check the bead line is even all the way round . Just as an add on , balancing will not solve a badly fitted tyre .
I seriously doubt a drive shaft is to blame , and worn steering joints would show up an issue constantly . The fact that you state a specific speed range , indicates (at least to me) it's a balance problem , and so more likely a tyre issue .

As an "for instance" , my own van , a small Suzuki , has play in the front nearside steering arm . Now quite aside from the fact that it does need sorting (not had time the do it) , as it is thrown up as an advisory on the mot for the last two years . Symptoms are similar to a wheel bearing , in fact it almost failed an mot when it was first discovered , as the inspector accessed a wheel bearing failure . But then i discovered play was in only one plane , horizontal , not vertical , indicated it was not a wheel bearing , and it passed . This does not show at all while driving !

 

[bugsymike]

Hmmm , you say you had the wheels re-balance , was that by the same company who fitted them , take it somewhere else ! . Eliminate the simple first .

We had a similar problem on heavy trucks many years back , which turned out to be a tyre incorrectly fitted . Check the bead line is even all the way round . Just as an add on , balancing will not solve a badly fitted tyre .
I seriously doubt a drive shaft is to blame , and worn steering joints would show up an issue constantly . The fact that you state a specific speed range , indicates (at least to me) it's a balance problem , and so more likely a tyre issue .

As an "for instance" , my own van , a small Suzuki , has play in the front nearside steering arm . Now quite aside from the fact that it does need sorting (not had time the do it) , as it is thrown up as an advisory on the mot for the last two years . Symptoms are similar to a wheel bearing , in fact it almost failed an mot when it was first discovered , as the inspector accessed a wheel bearing failure . But then i discovered play was in only one plane , horizontal , not vertical , indicated it was not a wheel bearing , and it passed . This does not show at all while driving !

If you read the whole post of symptoms and what has been checked, you may not be so quick to discount my diagnosis
Perhaps when OP has solved the issue he will let us know

 

[varesecrazy]

I had this on a car, got progressively worse, accelerating on uphill was the worst

It also had previously split a boot,

Changing that joint made an improvement

 

[airwave]

If you read the whole post of symptoms and what has been checked, you may not be so quick to discount my diagnosis
Perhaps when OP has solved the issue he will let us know

I'm sorry Mike , i wasn't discounting your diagnosis , i was actually just adding to check the simple things first . I would certainly recheck the tyres first , as a speed related wobble can often lead to something as simple as the tyres themselves .

However i do have to diverge from your advice , despite it being good advice as usual , something i would expect from an ex -professional . I personally , would be extremely worried about jacking a 3 ton vehicle up , and turning the wheels at high speed using an engine . That is to my mind is an extremely dangerous thing to suggest to any amateur . You have no idea of the posters capabilities , (no offence intended to the poster) , and is well outside the average weekend spanner whirrer remitt anyway . I know you have emphasized how you would go about this , but the average home mechanic has inadequate equipment to even jack these vehicles , let alone what you're suggesting . I know i don't , despite having an extensive tool kit , and the correct jacking and support systems for my own Motorhome rated at 3100kg empty . The handbrake (which incidentally is notoriously inefficient on these vehicles) would never hold it back , and should something go wrong with the vehicle falling off the supports . At the wheel rotational speed needed to show this fault up , it would move a significant distance in a very short space of time (seconds in this case) . There a very high risk of serious damage , or injury being the result .

Sorry Mike , but i can't endorse this particular course of action , and you can rest assured , that is from someone that has a very low opinion of the health and safety executive .

 

[bugsymike]

I'm sorry Mike , i wasn't discounting your diagnosis , i was actually just adding to check the simple things first . I would certainly recheck the tyres first , as a speed related wobble can often lead to something as simple as the tyres themselves .

However i do have to diverge from your advice , despite it being good advice as usual , something i would expect from an ex -professional . I personally , would be extremely worried about jacking a 3 ton vehicle up , and turning the wheels at high speed using an engine . That is to my mind is an extremely dangerous thing to suggest to any amateur . You have no idea of the posters capabilities , (no offence intended to the poster) , and is well outside the average weekend spanner whirrer remitt anyway . I know you have emphasized how you would go about this , but the average home mechanic has inadequate equipment to even jack these vehicles , let alone what you're suggesting . I know i don't , despite having an extensive tool kit , and the correct jacking and support systems for my own Motorhome rated at 3100kg empty . The handbrake (which incidentally is notoriously inefficient on these vehicles) would never hold it back , and should something go wrong with the vehicle falling off the supports . At the wheel rotational speed needed to show this fault up , it would move a significant distance in a very short space of time (seconds in this case) . There a very high risk of serious damage , or injury being the result .

Sorry Mike , but i can't endorse this particular course of action , and you can rest assured , that is from someone that has a very low opinion of the health and safety executive .

No problem
Of course you are perfectly right, something that is common practice in one area can be very dangerous for those less aware of the dangers and may not take suitable precautions to mitigate the risks.
With such a wide range of contributors to Forum it can be hard to balance giving information that works for everyone, sometimes I feel like I am trying to teach "Granny to suck eggs" and the next may be giving advice to someone who has never changed a wheel and it is going right over their heads.
Maybe like the TV shows "Don't try this at home folks"

As a possibly safer guide to locating the problem, a few things to check without jacking the vehicle up.
one is a visual inspection and vigorous shaking of both the drive shafts, if one has excessive movement within the joint CV boot it may be a pointer.
Another may be when it starts to shake see if one side wing/bonnet area is moving compared with the other. I have seen this where a tyre is statically out of balance. As opposed to the more common dynamically where the steering wheel may shake.
Like you, I have seen some horrendous tyre faults in the past. Although more in the days of cheap remould cross ply tyres. Although brand new Russian tyres were shall we say, interesting in the 1970s, they came from the factory eccentric so we had to fit new European tyres to sell the cars!
Another may be if it gets worse or better when going around a left or right hand curve in the road, the wheel on the inside of a bend is turning at a different speed so may cause the shake to alter.
In this case perhaps when he gets back he could suggest trying this to his garage if they cannot locate the fault any easier way.
My concern is, if who ever fitted the CV boot that possibly caused the problem was let loose in diagnosing the fault, it may not be an economical repair.

 

[varesecrazy]

I did it on a diesel estate (spinning wheels whilst on Axle stands)

Top gear foot to the floor.. disconcerting how quickly the gearbox driven speedo gets to 130 mph!

In hindsight removing the road wheels COULD have been safer...

BUT the shaft may not oscillate at the same frequency.. So the vibration felt through the floor pan may not have been so obvious

I didn't do this with the drives haft issue, as I already had suspicions of a dirt filled joint having expired

 

[bugsymike]

I did it on a diesel estate (spinning wheels whilst on Axle stands)

Top gear foot to the floor.. disconcerting how quickly the gearbox driven speedo gets to 130 mph!

In hindsight removing the road wheels COULD have been safer...

BUT the shaft may not oscillate at the same frequency.. So the vibration felt through the floor pan may not have been so obvious

I didn't do this with the drives haft issue, as I already had suspicions of a dirt filled joint having expired

Yes , if only one wheel off the ground the actual speed showing on the speedo can be double, so if speedo drive is on off side of diff housing and off side wheel off the ground, potentially even at 70 mph on the speedo that wheel can be doing 140mph

 

[bugsymike]

Yes , if only one wheel off the ground the actual speed showing on the speedo can be double, so if speedo drive is on off side of diff housing and off side wheel off the ground, potentially even at 70 mph on the speedo that wheel can be doing 140mph

Another problem when checking like this is if both wheels are off the ground with them not in contact with the road one may be doing a different speed to the other due to diff action.
Something else I have seen is with a car off the ground and engine running in neutral, one wheel may just turn a little you to drag in the gear oil I suppose and the car then throws up an ABS fault as it detects that one wheel at a different speed, though usually that code goes away on road test.

 

[varesecrazy]

Yes , if only one wheel off the ground the actual speed showing on the speedo can be double, so if speedo drive is on off side of diff housing and off side wheel off the ground, potentially even at 70 mph on the speedo that wheel can be doing 140mph

It was both wheels..
Yes it did go into the orange on tacho

 

[bugsymike]

It was both wheels..
Yes it did go into the orange on tacho

Now if you were on the Autobahn!!!

 

[Greasytrucker]

I had this on a car, got progressively worse, accelerating on uphill was the worst

It also had previously split a boot,

Changing that joint made an improvement

Just the same for me on a 2002 Mini Cooper R50, got progressively worse the more load on the engine, let off the gas and it went away. New complete shaft from J&R solved it. I just reached under and rotated the shaft forwards and backwards and noticed the freeplay was more than the other side, just drove it up a drop kerb for a bit of clearance for diagnosis