Bad Vibrations

[Gowf]

Hi, i am in need of some assistance in diagnosing a problem and wondered if anyone else has had a similar situation.
Ive got a legnum vr4 manual and it started to intermittently give vibrations through the chasis at around 80mph but only under acceleration. Its now decided that intermittent is boring and you can feel it all the time. Its quite a violent vibration, but doesnt appear to be coming from any wheel as such and is not at all present when cruising. cant really feel anything through the gearsitck or steering wheel.

I havent had chance to jack it up yet for a proper look underneath to see if its a propshaft bearing or similar. Has anyone experienced this? Can you help?

[BraindG]

Does it happen at any other time? and does it only happen when you accelerate?

[Gowf]

Originaly it was only at speed, but now it can be noticed whatever speed but only under acceleration. Every now and again it wont do it, it will just accelerate smoothly, but its definately getting worse. Any thoughts?

[BraindG]

hmm, might be something similair to what i am experiencing. (I also beleive The Vee suffers from it, or atleast used to)

We all have Manual cars aswell btw.

When I accelerate It feels like a judder, a vibration if you will. Again, this only occurs when I accelerate and at no other time do i experience this judder. Also i feel it more at low speeds, on motor way i dont really feel it that much.

Now, I initially thought this was relating to my clutch, when I changed my clutch a while ago the problem went away, but... what i forgot was that i changed one of my front diveshafts at the same time.

Now, don't laugh, but i remembered this in a dream where i solved this judder problem. To confirm i checked previous posts, and found the one where i changed front driveshaft. clutch change start sept -- shaft change end aug.... Odd huh, isn't dreaming cool.

Anyways, in my dream i figured out that the judder was due to the drive shafts. Now, I can't really remember what exactly the problem was, but I have a feeling it was related to the wear on the inside of the Green Housing at the end of the driveshaft. Now, obviously this was in a dream, and not concrete evidence. So if anyone has any suggestions as to what in a driveshaft could judder that would be super.

Do you have any other kind of noises coming from the car, for example going round corners, rubbing, whirling or anything?

[Gowf]

I did have an evil noise coming from the back when the ayc came on. But since changing all the trans oils its stopped. Other than that, there is an odd noise when its idleing in neutral. Its a clutchy type noise, but its not bad. You can basicaly hear the clutch spinning, unless you press the pedal obviously. and thats only from outside the car. I think that i may need to sleep more, as dreaming may be the answer! But you recon driveshaft? when you had problems could you detect play in the shaft by hand? or was it due to cornering and a cv style noise?

[BraindG]

there will always be play in drive shafts, deffo in and out.

Im not sure, but its quite a possibility that it is the drive shaft, im sure some of the other guys will have their ideas though. Lets wait and see what others say.

[Spirit]

May not apply but seems quite a few VR4's seem to suffer from wheel wobble type effects around the 80mph mark. I have had it several times, and at 75mph it goes and 85mph it goes. Have you had the wheels balanced ?

[Gowf]

yeah, its definately not wheel balance, as its getting worse and the vibration is only there when accelerating. it would always be present at certain speeds if it was balance. I'l endevour to get underneath it and see if i can find anything obvious.

[Kieran]

The only other thing that springs to mind is a collapsed engine mount. Is there any more noise at idle?

Stick your head under the car - is the gearbox sat ON the crossmember, rather than slightly above it? If you (with a warm engine!) give the throttle cable a good series of yanks, does the engine rock about?

[tig202]

When the vibration happens, have a good look around the cabin of the car. Sometimes you might be able to pinpoint it by the way a certain 'part' of the interior vibrates. Front driveshafts will produce a vibe through the steering wheel as they are connected, a vibe through the rear seats could mean there is something amiss at the back end. Best get someone to sit in all seating posistions of the car to see where it is coming from, then try to diagnose!

Just my tuppence worth!

[Mikesone]

My Leggy did have to have the driveshafts replaced at 130,000miles (although they said it was likely that is was just the longer of the two shafts that had gone west.)

The symptoms were vibration through the car (you could feel it through the steering, but it was not a violent shudder) the vibration was most noticeable if you slowly accelerated between 40 to 70mph.

Also had a front wheel bearing go west, that vibrated through the car as well, and got worse at speed, identifiable as it faded in and out as you went round corners.

Not sure if thats any help.

Regards

[Gowf]

It does seem from what you have all said to be shaft related. However, i put it on axle stands today and got someone to accelerate while i was underneath. There is definately no shudder at the back end from what i could see, but there was at the front. The gearbox itself was rocking, not hugely but possibly enough to give a vibration. So before i go down any shaft route i think i may as a matter of course change the engine and gearbox mounts, as it doesnt seem to effected by cornering or speed, only acceleration. strange though when sat in nuetral it doesnt do it, only when under load. Has anyone got any advise on where to get mounts from, and whether to use standard or go for an uprated poly mount, if you can get them?

[tig202]

Tis sounding more like a propshaft related vibe bro

[BraindG]

Tis sounding more like a propshaft related vibe bro

What can go wrong there? what might it be if it is?

[tig202]

What can go wrong there? what might it be if it is?

Plenty of things Baz m8,

The propshaft is supported by a bearing encased in a rubber mounting, both of which can wear/deterioate, the prop has a few cv joints mounted along it all of which can start to run dry and also as the whole propshaft is a balanced rotating item any damage incurred to it will put it out of balance.

now i have explained this im off for a stella or 6

[BraindG]

considering how easy it is to change.... im wondering if its worth changing with wouters car... for exmple to see if my problems go..

[zedy1]

Prop, Diff Or Transfer Box (long Shot But Possibly Flywheel)

[Gowf]

i did originaly think prop bearings. But it didnt appear to be vibrating whilst looking at it. I know that is no clear indication, but the only way to check i suppose is to try another one and rule it out. Only problem being, where to get one to try as new may be a huge cost and might not cure the problem. does anyone have a spare that they would be willing to allow me to try?

[pitslayer]

i posted something up on this in the suspension forum......get the front end off the floor, grab the wheels move them left to right but only slightly....kind of like if your checking the wheel bearings, if you hear a slight clicking, check your steering arm....from the hub there should be an arm that goes to the bulkhead, and where that arm meets the bulkhead part of the steering rack is a knuckle, mines very loose and causes vibration past 75mph, and goes when you turn right or left as the slack is being taken out of the joint, so check that aswell....

[Gowf]

Well finaly diagnosed problem today. Drivers side front shaft inner joint. Really really bad now, so much so that you can hear it, and vibration is always there. Thanks for all the ideas and help, muchly apreciated!
Where would you suggest to try and get a shaft from, other than of course the £400+ mitsi price?