Vibration at Speed

[Haydo]

G'day all,

I know there's a few posts on this but l'll give it a crack again...

I'm getting serious vibration over 85km, nothing noticeable at lower speeds.
I've had the wheels balanced & aligned a couple of times. Last time they were rotated.
The steering wheel goes nuts shaking from side to side but I reckon I can feel the vibe through the seat & even the accelerator pedal at times too.

The weird thing is crusin down the freeway 100-120km the steering wheel will be shaking like mad, then all of a sudden it will be as smooth as, no vibe for about a minute or so then it starts going spastic again. This makes me think its something out of the ordinary but maybe I'm wrong.

[Adds_05]

maybe some bushes need replacing,front castor etc? or wheel bearing?

[Haydo]

Thanks for the reply Adds.
I should have mentioned, front caster bushes have been replaced already. As for the bearings they seem tight but while I had the car up I gave the wheels a spin... about once per rev. there is some friction. I would have had a better look if the mrs wasn't breaking my balls... but just by that maybe the rotors are warped? Come to think of it I reckon I can feel it when braking lightly. Whaddya think?

[calais24/7]

just an idea mate, get someone else's front wheels to borrow, ones that drive fine on their car and take it for a spin. I had the same problem but mine was constant at 80+ it turned out it was the tires, they wernt low and what i thought were a good brand to. so yeah borrow some other wheels and try that out? saves you buying new tires if it isnt the tires

[c2105026]

Check:
- Bushes
- Wheel bearings
- steering rack

I had a similar issue on the VB. If its VT, the problem could be in the tailshaft. Problem on the VB was solved via a new set of tyres.

[tdirago]

Maybe a wheel or two is buckled, if you get the chance have a look at that

[Mohi]

mine had the same trouble and then found out one of the wheel was buckled , tell the tyre shop people to only run the wheel on the balancing machine without the tyre and they will find out which one is it.

[Haydo]

just an idea mate, get someone else's front wheels to borrow, ones that drive fine on their car and take it for a spin. I had the same problem but mine was constant at 80+ it turned out it was the tires, they wernt low and what i thought were a good brand to. so yeah borrow some other wheels and try that out? saves you buying new tires if it isnt the tires

Yeah, I've got a set of VT Clubsport rims in a mate's shed but that's at the arse end of nowhere... looks like I'm goin for a road trip next weekend.

Check:
- Bushes
- Wheel bearings
- steering rack

I had a similar issue on the VB. If its VT, the problem could be in the tailshaft. Problem on the VB was solved via a new set of tyres.

I miss my old VC... the old interceptor rims would come in handy about now. Besides caster bushes what else should I be looking at?

Maybe a wheel or two is buckled, if you get the chance have a look at that

They look OK visually anyway, I'll be spewing if they are. I reckon the friction is between the rotor & pad though, would a buckled rim cause that?

Thanks for the replys fellas. I'll have a better look this weekend.

[Haydo]

mine had the same trouble and then found out one of the wheel was buckled , tell the tyre shop people to only run the wheel on the balancing machine without the tyre and they will find out which one is it.

Thanks for the tip mate, I'll be pi$$ed off if its a rim though.

[tdirago]

I got my wheels off ciddyau (user of this site) and the two front wheels were badly buckled and i get the vibration at higher speeds, but to combat this they put the wheels at the back and the best two at the front. Had to get two new tires as well as one was deformed and other had a split

to bad he forgot to mention this stuff to me and i had to learn the hardway

[Jonno]

Hey mate I aggree with everyone about the rim/tyres
Where u from I could help...

[calais24/7]

yeah if your anyone near canberra i can lend you a couple of chasers or wheels or something

[calais24/7]

I got my wheels off ciddyau (user of this site) and the two front wheels were badly buckled and i get the vibration at higher speeds, but to combat this they put the wheels at the back and the best two at the front. Had to get two new tires as well as one was deformed and other had a split

to bad he forgot to mention this stuff to me and i had to learn the hardway

i would have given him a ring if i was you

[Circlotron]

Son's '96 Magna has pretty much identical vibration. We are getting to think it is the shock absorber / damper in the front strut.
The mass of the wheel and the bounciness of the tyre on the road has a natural frequency and if the rotational speed approaches that frequency and there is no damping to speak of then it is very likely the wheel will hop up and down violently.

[graham7773]

If all else fails, check your tie rod ends. Just a little play can do exactly what you have described ie vibration then all gone then back again. I don't know about now but it used to be called "tram tracking". Hit a little bump that would not normally worry the car and get light to mad vibration and maybe even the steering following small ruts in the road. Easy fix though. new tie rod ends are cheap as chips.

[Rhin0o8]

If all else fails, check your tie rod ends. Just a little play can do exactly what you have described ie vibration then all gone then back again. I don't know about now but it used to be called "tram tracking". Hit a little bump that would not normally worry the car and get light to mad vibration and maybe even the steering following small ruts in the road. Easy fix though. new tie rod ends are cheap as chips.

youre right on the money there.

I replaced my tie-rod ends in my VT just this last Friday.
I had constant viabration above 90kmp/h

30 minute job to replace and it drives a hell of alot better
cost no more than $40 a pair. ALWAYS change both sides at the same time

OP, check and replace tie-rod ends

[tdirago]

i would have given him a ring if i was you

he lives less than 5kms away from me, i dropped off the beaurepairs invoice with a description of what was wrong and how much i paid at his house and he still refused to pay a cent. had to pay to get the other tires turned inside out beacuse they had walls lol

ah well, i was ignorant. not anymore

[Haydo]

If all else fails, check your tie rod ends. Just a little play can do exactly what you have described ie vibration then all gone then back again. I don't know about now but it used to be called "tram tracking". Hit a little bump that would not normally worry the car and get light to mad vibration and maybe even the steering following small ruts in the road. Easy fix though. new tie rod ends are cheap as chips.

Awesome specific response Graham! How do I give ya some feedback points? Outer tie rod ends look easy enough to replace so I'll give it a crack. I guess I'll need another alignment after I do the job... Thanks for the confimation Rhino.

Appreciate the offer for help Jonno, I'm prolly about an hour away from you (about the same distance to my mates shed where my other rims are). Do you get extra strokes with a supercharger? LOL... Suck, squeeze, bang, fart... ping! 5 strokes x 6 cylinders=30! LOL

Still reckon my rotors are warped though... how's this idea for a test?
I took a piece of chalk (from the Darts scoreboard) & marked the rotors about every CM then pushed the car a couple of metres, really slowly so I didn't use brakes to stop, then had a look. Chalk marks rubbed off on about 1/4 to 1/3 of the rotor. Similar on the other side.
Could shagged tie rods cause this? I'll change 'em anyway.
Was the idea stupid?

[Haydo]

Hmmm... No comments? Maybe it was a stupid idea then.

Update:
Changed the tie rod ends which definately improved the feel of the steering but didn't fix the vibrating at speed. I might be dreaming but it may have actually accentuated the problem. Still, it was worth the $70 spent at Repco. Getting a balance & alignment Monday so we'll see what difference that makes - I'll get 'em to balance the rim withouht the tyre like Mohi suggested.

Any other ideas fellas?

[c2105026]

with the rotors - does the steering wheel shake under vibration at moderate speed eg. going from 80-60? If not then its probably no the rotors. I still reckon it could be they tyres. How much mileage is on your current tyres?

[Kernal]

Its one of your rear tyres that isnt exactly round at high speed. Swap your spare with them one at a time to eliminate the good tyres from the bad tyre, then just replace the bad tyre. This happened to one of my rear tyres after i had put over 2000ks on it. its just a defect.

[RiCeY]

It wont be rims or tyres if the vibration comes and goes, they would cause a constant vibration. Buckled rim would be obvious when balancing even with tyres fitted to rims.

Wheel bearing will be noisy and the noise will change when you veer left to right, also raise the car and grab the tyre at the top and bottom and see if theres any play in the wheel pushing the top and in pulling the bottom out and vice versa.

Tie rod ends worth a look, if you replace them measure how much thread is visible on the old ones and fit the new ones the same, saves realigning. (Presuming the new are identical to old)

[RiCeY]

Oh and brake shudder is caused by warped rotors/excessive runout which is common on commodores and caused by overheating the brakes. Fixed with a skim if theres enough meat left on them and wise to fit new pads to get maximum performance.