Cold Vibration?

[V8Symphony]

Hey all,

I've got a vibration in my VXII Calais, and was wondering if anyone else has had the same problem, and if so what was the cause?

When you first start the car in the morning from cold, and then get out on a normal street and cruise at constant throttle, the car has a vibration coming through the chassis, mostly felt in the seat of your pants.

It's probably about 3 - 6 Hz, and only does it at between 50 - 60 km/h, for the first 5 - 10 min after a cold start.

Any ideas?

[Smitty]

Hey all,

I've got a vibration in my VXII Calais, and was wondering if anyone else has had the same problem, and if so what was the cause?

When you first start the car in the morning from cold, and then get out on a normal street and cruise at constant throttle, the car has a vibration coming through the chassis, mostly felt in the seat of your pants.

It's probably about 3 - 6 Hz, and only does it at between 50 - 60 km/h, for the first 5 - 10 min after a cold start.

Any ideas?
what rpm?
does it do it at the one speed or at a particular set of revs...?
want to see whether road speed or engine speed related
and does it go away completely after 5-10 mins?
more info would be good....

[The Warden]

Could be your tyres. I get a vibration for the first 1km or so, there was a thread about this a while back, not so much the tyres going out of round from memory, but the construction and heating of them I think. Try a bit more pressure, say up to 38-40psi cold for a day or two, see if that makes any improvement at all.

Cheers,
Gordie

[V8Symphony]

It's speed related, although I can't say whether it does it in drive, as I drive around town in 3rd and only change up on the highway.

At a guess on the RPM, it would be only just above idle, say 1500 rpm?

It only happens between 50 and 60 km/h and disappears completely within 10 mins

cheers

[seldo]

I'm probably with The Warden on this one. Mine does the same thing but only immediately away from rest. I'm convinced it's just the coarse tread blocks on the tyres being a bit stiff until they warm up...:eyes: you know how it is on those cold mornings...:doh:

[SV8VY]

My Vy does this when you first start it and drive off.....the abs is doing a test

[Smitty]

It's speed related, although I can't say whether it does it in drive, as I drive around town in 3rd and only change up on the highway.

At a guess on the RPM, it would be only just above idle, say 1500 rpm?

It only happens between 50 and 60 km/h and disappears completely within 10 mins

cheers

mate
I am gunna agree with the other boys here.....
tyres....
sitting overnight, the tyre gets a flat spot,that doesn't go away
until the tyre starts to warm up..after about 5 mins or so driving
drive slow (20,30kmh) and you probably won't feel it...
drive at 60kmh...you will
you can try a little more pressure..take it up to 35, 38psi
and see if it goes away...
but I doubt it

hth

[V8Symphony]

I'll give the tyres a bit more pressure, as you guys suggested.

I'm too busy having fun in it now, just got it back after it's first edit at power torque.

VERY HAPPY!!!!

Grin factor 110%!!

[blk vy ss ute]

what did it run on the dyno?

[V8Symphony]

got it up from 183rwkw to 204rwkw, with just a cat back exhaust, Monaro CAI and K&N filter.

pretty damn happy with that!

[Mongy]

mate
I am gunna agree with the other boys here.....
tyres....
sitting overnight, the tyre gets a flat spot,that doesn't go away
until the tyre starts to warm up..after about 5 mins or so driving
drive slow (20,30kmh) and you probably won't feel it...
drive at 60kmh...you will
you can try a little more pressure..take it up to 35, 38psi
and see if it goes away...
but I doubt it

hth

You are exactly right on the money with this one.