Vibration at 70 - driveshaft?

[chinkostu]

plagued by vibrations whenever the car hits 70. feels like an out of balance wheel but has only just really come on in the last week. tyres are all inflated and no missing weights I do also get a bit of a groan/bump if i'm on full right hand lock (EG, parking)

a quick googlefu shows it could possibly be the driveshafts? the boots look ok though, no tears and no grease splattered everywhere

[Gibbo2286]

Get the wheels re-balanced first almost always the problem, rarely the driveshaft.

[Mandrake]

Also check for slack in the track rod joints - any slack here can magnify any tiny (and normal) wheel imbalance, making it seem much worse than it is.

If you corner slightly and the vibration goes away one of the track rod joints probably needs replacing. (And wheel alignment resetting afterwards of course)

[darbuck]

check tyre age, mine had same problem tracked and balanced before changing tyres made no difference but discovered small blister in old tyre thread got new 215/60/16 's much better now it still jumps sometimes on turning but much rarer check all bushings as well as drop links added to it aswell.Also if this is the same car as in wheel hub post it could be the wheels coming loose on the hub in which case it could be dangerous to drive until the hubs have been ruled out which should be your first port of call.

[Peter.N.]

The inner driveshaft joints can cause vibration but usually only at high mileage and when hot. I had this problem on a CX at something around 200k miles. The inner joints wear but all the while the grease is reasonably viscous it doesn't cause a problem, it was only after I had done about 100 miles or more that I noticed it, the grease thins and fails to keep the joints central.

Its still more likely to be a wheel balance problem though at about 95% of these are. You can get ply separation on the tyre which will not necessarily show up on a balance test.

Peter

[chinkostu]

Good to hear guys. Front tyres are getting close so will get them replaced and see if it helps!

[wurlycorner]

Excessive wear in the CV joints is easy to check for though, so it's also worth checking - lie under the car, grab the driveshaft and give it a good yank about. You'll see if you have movement at one end in comparison to all the others.
Sometimes you can detect early signs of wear in the outers if you have the wheel jacked off the ground with the gearbox in gear (engine not running! ) grab the wheel and wiggle the rotation back/forth (so you don't actually rotate, you're just checking for backlash in the change of direction). You might see or feel it, or possibly even hear a click.