Vibration at Motorway Speed
 

Car is 2007 XC90 D5 SE Sport (Auto) on 190,000 miles.

Any suggestions on what the most probable suspects are for the following vibration:

Intermittent whole car vibration - generally when doing circa. 70 mph. Could easily be mistaken as symptoms of driving on a badly surfaced road.

On a recent 4hr journey from London to Exeter, this vibration would occur every 20mins or so. Doesn't seem to disappear if you accelerate through - although I will need to experiment a bit more to be sure.

Oddly - the first bout of the shakes only seem to occur once you've done about 15-20 mins of driving (i.e. once something's got hot).

Absolutely no shake or pull coming through the steering wheel (note: I think the car is fitted with speed variable rack).

The vibration makes everything in the door pockets and centre console rattle. All sorts of trim start to clatter - basically whole car rumble. Definitely nothing felt through the wheel.

A very quick inspection at my local garage - the front CV joint on the prop shaft has a tiny amount of play. In my non-mechanical opinion - just seems odd that it would cause an intermittent problem.

Car has an occasional Steering Wheel Angle Sensor fault. Also to note - fluids were very recently changed to both differentials and the Haldex unit (with new filter) - all by my local independent.

Any thoughts on likely contenders?

These can be quite hard to diagnose.

Firstly I would rotate the tyres (fronts to back etc) and get the balancing checked. Also check carefully that the tyres are perfectly round - i.e. they have no bubbles, bulges or deformation to the carcass from storage? Check tyre pressures too - try over and under inflating them slightly (briefly to test)

If that makes no difference (if it was a rear tyre you might then feel it through the steering if it was then at the front) then it gets tricky.

Vibration through the whole car at speed has to be caused by a rotating mass either our of balance or not mounted correctly.

- Check all wheel bearings carefully

- Check wheel bolts are correctly torqued and there is not contamination on the mating surfaces of the wheels or hubs

- Check the propshaft mountings and bearings under the car

- Get the car on a 2 post ramp (i.e. in the air and all four wheels off the ground *securely* ) then run the engine so the wheels turn at speed - can you see a single wheel moving the suspension? (You may not get the rears to move as quickly)

It might be hard to find but I doubt it will be too expensive to fix.

Check the rear Nivomats (shock absorbers) for leakage by peeling back the rubber boot. Can give vibration as described.

My leaky shock absorber was hidden because of this boot, its very good at keeping crap out... and hydraulic fluid in.

And I've had a rear sticking clapper that cause loud intermittent rumblings vibrations at those speeds. It can come and go.... as the calliper sticks then unsticks. When you get the vibration, try and pull over and check if the rear brake calliper is hot and or disc is hot. watch your fingers though ! they get scalding hot.

Also check that you haven't got a binding brake. Next time you get vibration pull over as soon as you safely can. Feel (safely without burning yourself) if you've got one wheel hotter than the others. Expect to smell brake dust too as you go round the car.

SNAP. :teeth_smile:

Might have to do with engine operation. After 20min driving the engine gets fully hot and some worn sensor may not like it.

Whole car vibration can also come from rear wheels/axles/awd

Just careful with mechanics suggesting this and that

+2 for binding rear brake.

Thanks everyone for your suggestions.

I will take the car on a good long run this week - and report back.

Well...lot's of you guessed correctly.

Nearside rear caliper must be sticking - incredible amount of heat from that corner. Even the alloy wheel was roasting hot.

Thank you everyone for all your help.

Have a look at this thread:

https://www.volvoforums.org.uk/showt...t=rear+caliper