strange vibration

[tonyd106]

Hi all, basically i was on the motorway half hour ago and i put my foot down to pull out and over take a few slower moving cars. As i got to 80ish the car judered and vibrated loads (as if your driving down the white lines on motorways).
I pulled back into the slow lane and slowed down to 60 and the vibrating went away and didn't come back till i tried to go over 75 (to see if it would happen again).

Any one got any ideas?

 

[McGherkin]

Wheel balancing/tracking?

 

[tonyd106]

I thought that, but i done a 340 mile round trip on the weekend 90% was on the motorways, went around the 70-80 mark a few times and it never happened once.
The car pulls very slightly to the left when i let go off the wheel, so im guessing the tracking ain't that bad.

Im hoping its just the wheels that need balancing.

 

[McGherkin]

Normally it's just because a wheel weight's fallen off

 

[SimplyEd]

Was it only while accelerating or while cruising / decelerating at that speed too?

 

[tonyd106]

Only when accelerating Ed

 

[tonyd106]

Hopefully thats all it is

 

[SimplyEd]

Only when accelerating Ed

I'd say it was driveshaft / CV boot related then, but it's strange it only does it at that speed. Must be a very slight issue magnified by putting load on the running gear.

 

[tonyd106]

Whats the easiest way to test to see if its this? Or should i just take it to a garage and ask them to have a look?

 

[SimplyEd]

Whats the easiest way to test to see if its this? Or should i just take it to a garage and ask them to have a look?

If it's slight then it's not going to be visually obvious I don't think; worth having an initial inspection though. If it's convenient to have someone look at it then I'd recommend that.

 

[tonyd106]

Ok, i'll try get the mechanic next door to have a quick look at it tomo.

Thanks for the help and i'll update tomo.

 

[tonyd106]

I got the wheels re balanced last week and all was fine

however when I was driving home yesterday I noticed the vibration had come back but not as bad.
Could one of the weights fallen off somehow?

It's strange as it's been perfect for a week.