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Vibrating 964

Emmjayeff

Member
Joined
14 Mar 2016
Messages
9
I recently bought a 1990 C4 and I am delighted with the car and would be even more so if it wasn't for the vibration that I get at speeds between 120-140kph. The garage I bought it from have gone through a long list of things they have done to try to resolve the problem but none of them have done the job. Here's the list:
Balanced the wheels both on and off the car.
Tried different tyres.
Changed one rear wheel which they thought wasn't running true.
Changed the coils and shocks on the back of the car.
Changed both drive shafts.
Replaced one control arm bush.
Took the drive shaft off tested it and reassembled it.
Any other suggestions would be gratefully received
 
Where the vibration coming from - through the steering wheel, gearstick, body :dont know:

Engine mounts OK?
 
It appears to be coming from the wheels and as a result you feel it in the steering wheel. It does have a tendency to come and go, so you might be doing 130kph and get a vibration then the next time you are at that speed you won't get it and then it reappears. I am asking the garage if they checked the engine mounts. Thanks for your help.
 
Would be well worth putting another set of wheels on, you might have an issue with one of the front ones?
 
Hi,
I think I might try looking at the engine mounts as the wheels seem to be fine. They were the first port of call but were deemed perfect after being balanced both off and on the car.
My guys at the garage didn't mention that they had looked at the engine mounts but it seems to make sense as the vibration isn't consistent and it could possibly be the mounts that are affected differently according to the circumstances. I hope this makes sense, thank you for your input, I will keep looking and if I get a result I will let you know.
 
Basic rule of thumb .. rear wheel imbalence will cause a vibration through the car .. you may feel shakes or a tingle / buzz through the seat or pedals that sort of thing . car may also feel a little unstable .

Front wheel imbalence will cause steering wheel vibration .

Do you only have steering wheel vibration ?

You are slightly high for wheel imbalence although it could be possible .. i assume you can drive through the vibration ( go faster and it stops ? ).

You have said all wheels have been balenced so we can discount that .. my thought was the wheels are not the only thing spinning at speed .. the discs are as well BUT you have said the wheels have been balenced ON the car and this would stop vibration if it was discs.

I would ask that you confirm this as a disc imbalence seems plausible.

The problem if you only have steering vibration would imho be comeing from the front suspension / wheels .

Something out of balence is always out of balence it wont come and go so that tends to lead away from it being wheels / discs so ive come to the one thing i can think of ..

A sticking front caliper is causeing a slight bind and applying the brakes more on one side than the other .. if i was looking at the car then thats the next thing i would check i feel.
 
Hi,
Thanks for your response. The wheels were definitely balanced on the car in order to eliminate them as the source of the problem. I get the vibration through the steering wheel, as opposed to the gear lever for instance. I will try tomorrow and see at what speed the vibration no longer occurs and let you know. The rear suspension, shocks and coils were changed for new, maybe the fronts need changing too.
 
I have often wondered if aftermarket locking wheel nuts can cause this type of effect since 4 will be lightweight alloy nuts and one a heavy tempered steel unit. Just a thought.
 
masher964 said:
I have often wondered if aftermarket locking wheel nuts can cause this type of effect since 4 will be lightweight alloy nuts and one a heavy tempered steel unit. Just a thought.

No they dont .. too close to the centre of rotation really but an interesting idear :)
 
Demort said:
masher964 said:
I have often wondered if aftermarket locking wheel nuts can cause this type of effect since 4 will be lightweight alloy nuts and one a heavy tempered steel unit. Just a thought.

No they dont .. too close to the centre of rotation really but an interesting idear :)

Depends what size/weight they are. I recall years ago pater had a Granada with 'after market' locking nuts and we had to have the wheels balanced on the car to stop the wobble. Having the wheels done off the car were perfect but clearly affected by something when they went back on which we put down to the nut :what:
 

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