Violent shaking during motorway driving
Discussion
Hi all looking for some mechanical advice, I have a little 1.5l 2007 subaru impreza 4wd, car has been perfect for daily use, however if I sit on an empty bit of dual carriageway for 5 min ish the car starts shaking, this starts with a little vibration but soon turns into it feeling like a washing machine with a brick inside, this forces you to stop and the violent shaking stays the same all until you completely stop, only the frequency changes. Wheels have been balanced, car taken to a good local garage and nothing found, diff oil changed and its still doing it, seems to be coming from the rear I believe, after it starts nothing will stop it, neutral, braking, speeding up, handbrake on or swerving, I have managed to make it not start doing it by swerving over the dual carrigeway every few minutes but obviously this isnt ideal, Thanks for any help (2007 subaru impreza, 100,000 miles)
Robert
Robert
Could it be the handbrake - if it's the type that has cable operated shoes inside the rear disc? Maybe it's been adjusted too tight or is sticking against the drum part of the disc, and the eventual heat build up leads to the juddering?
After this has happened, are any of the rear wheels hotter than the other? Doesn't explain why swerving solves it, unless that's sheer coincidence.
If it's possibly the handbrake adjustment, usually theres some sort of screw you can adjust at the handbrake to slacken it off a bit, and test it.
My only experience of similar was I contaminated one of my rear handbrake assemblies while resolving a sticking issue, but as it was going in for the MOT the following day I took it for a drive with the handbrake slightly applied (to try to burn the contamination off). Don't judge me people, it worked. But after driving at speed for a bit the sudden noise and juddering was very quick to take hold.
After this has happened, are any of the rear wheels hotter than the other? Doesn't explain why swerving solves it, unless that's sheer coincidence.
If it's possibly the handbrake adjustment, usually theres some sort of screw you can adjust at the handbrake to slacken it off a bit, and test it.
My only experience of similar was I contaminated one of my rear handbrake assemblies while resolving a sticking issue, but as it was going in for the MOT the following day I took it for a drive with the handbrake slightly applied (to try to burn the contamination off). Don't judge me people, it worked. But after driving at speed for a bit the sudden noise and juddering was very quick to take hold.
I'd go for propshaft bearing mount/Bush (if there is one) my pal had it recently on his VW toureg.
95% of the time would drive fine until it hit a particular speed and the whole lot would go out and vibrate horrendously. Once off centre that's it, it stays there due to centrifugal force.
The bearing on the propshaft is in like a rubber donut/Bush that is in itself in a housing bolted to the car structure. It degrades over time and stops holding it centrally, manifesting itself in the above. Well known issue on touregs (and derivatives).
95% of the time would drive fine until it hit a particular speed and the whole lot would go out and vibrate horrendously. Once off centre that's it, it stays there due to centrifugal force.
The bearing on the propshaft is in like a rubber donut/Bush that is in itself in a housing bolted to the car structure. It degrades over time and stops holding it centrally, manifesting itself in the above. Well known issue on touregs (and derivatives).
I had this happen to me once on a BMW I owned.
Turned out to be one of the front callipers that was damaged and I think it was causing some binding. It scared the hell out of me and didn't do it again on the specific trip I was on but was replaced very soon after.
I can't remember if braking addressed it or not.
Turned out to be one of the front callipers that was damaged and I think it was causing some binding. It scared the hell out of me and didn't do it again on the specific trip I was on but was replaced very soon after.
I can't remember if braking addressed it or not.
Could be anything, but I've changed plenty of prop shaft center support bearings that gave the same symptoms you describe.
https://www.youtube.com/watch?v=HKM_SRsANos
https://www.youtube.com/watch?v=HKM_SRsANos
Matt_E_Mulsion said:
It's bizarre that it takes five minutes to start, that would say to me that something has got to get hot. If it was a brake (any brake) surely there would be a burning smell?
The grease in a bearing. When cold it's viscous and acts as a damper, as the temperature rises the viscosity drops.Two suggestions, though i too would be looking at brake sticking/seizing issues.
1, dampers past their best.
2, i've had this myself once with a newly fitted set of rather expensive aftermarket wheels, the selling shop of which failed to fit or even source the correct spigot rings so only the wheelbolts were locating said wheels.
Once the vibration set up it was awful, but didn't manifest itself till after an hour's running.
To be fair the wheels were only slightly off centre with just the wheelbolts and maybe not all 4 were out anyway, i think that whilst one was oscillating it barely noticed but after a while the natural changes in rotation speed as you take corners will bring two or more wheels into the same oscillations cycle, which is when it manifested itself spectularly.
cue a 45/50 mph cruise home stopping to make an unnecessary turn now and again to alter wheel positioning relative to one another.
If you jack the car up and securely block it up, then allow the wheels to spin you'll probably be able to see anything untoward, removing a wheel and how it sits of the hub will confirm one way or another.
In my case i jacked a front wheel up spun it up and the problem was immediately apparent.
hmm and 3.
Are the tyres the the same size type and tread depth all round, if not the centyre diff is working overtime and could be overheating, also whilst on the subject check all the transmission oils, for level and cleanliness.
1, dampers past their best.
2, i've had this myself once with a newly fitted set of rather expensive aftermarket wheels, the selling shop of which failed to fit or even source the correct spigot rings so only the wheelbolts were locating said wheels.
Once the vibration set up it was awful, but didn't manifest itself till after an hour's running.
To be fair the wheels were only slightly off centre with just the wheelbolts and maybe not all 4 were out anyway, i think that whilst one was oscillating it barely noticed but after a while the natural changes in rotation speed as you take corners will bring two or more wheels into the same oscillations cycle, which is when it manifested itself spectularly.
cue a 45/50 mph cruise home stopping to make an unnecessary turn now and again to alter wheel positioning relative to one another.
If you jack the car up and securely block it up, then allow the wheels to spin you'll probably be able to see anything untoward, removing a wheel and how it sits of the hub will confirm one way or another.
In my case i jacked a front wheel up spun it up and the problem was immediately apparent.
hmm and 3.
Are the tyres the the same size type and tread depth all round, if not the centyre diff is working overtime and could be overheating, also whilst on the subject check all the transmission oils, for level and cleanliness.
Edited by Smint on Monday 16th May 07:21
I’ve had that myself on a BMW and - a binding disc with siezed caliper and warped disc. Took me a day of exactly what you have to figure it out as the symptoms were strange - sudden onset of shaking at motorway speeds but not so much at low speed. The 2 hour journey home was a nightmare and it was only the smell of a cooking brake (o/s front) that gave it away.
Bought a set of callipers/discs from a Sunday opening motor factor for £175 (inc exchange callipers) and 2 hours later job done.
Bought a set of callipers/discs from a Sunday opening motor factor for £175 (inc exchange callipers) and 2 hours later job done.
Unfortunately everyone has a different opinion of what it could be & many are plausible.
For me it sounds like wheel bearings but one thing I would say to you whatever the cause..........
Get it somewhere competent for a second opinion including a test-drive as it is quite clearly potentially very dangerous!
I say wheel bearings as the act of swerving could redistribute wheel bearing grease/bearing internals just enough to stop the issue from coming up, I know of nothing else that would explain everything you say.
For me it sounds like wheel bearings but one thing I would say to you whatever the cause..........
Get it somewhere competent for a second opinion including a test-drive as it is quite clearly potentially very dangerous!
I say wheel bearings as the act of swerving could redistribute wheel bearing grease/bearing internals just enough to stop the issue from coming up, I know of nothing else that would explain everything you say.
bolide said:
Sounds a bit like the Jeep Death Wobble Americans talk about. So it's related to worn suspension bushes creating a resonant frequency in the suspension
Might be worth putting a GoPro under the car watching the suspension links to see where the vibration originates from
Good suggestion that, alternatively get someone else to drive your car and you follow in another and watch what happens, this can be an excellent method for diagnosing tricky issues, for example, we've all seen cars with obviously worn shockers bouncing their way unceasingly down the road and the odd vehicle crabbing sideways.Might be worth putting a GoPro under the car watching the suspension links to see where the vibration originates from
Talking of worn suspension and a 'death wobble', i had exactly that on an artic tractor unit back in the 80's, when a set of road undulations set up the right resonance at a speed above 50mph one front wheel would continue to bounce up and down at a rate that had to be seen (and felt through the steering) to be believed, slowing down to 20mph or less was the only was to stop it.
It was cured by disconnecting the autolube (piped oil delivery system lubing the whole chassis and suspension) to the front spring shackles and fitting grease nipples instead and steam cleaning the multi leaf front springs so they returned to dry and regained more resistance, obviously by now the front dampers were worn out so new dampers too.
I tend to agree with the others though, that my first thought is a brake seizing issue, sadly regular brake servicing seems to be a thing of the past.
Another here for checking brakes - I had a slightly binding front caliper on my MX5, caused vibrations and wheel shimmy on the road. After removing and cleaning it all it was fine - dirt had accumulated where the piston/claw assembly slides against the fixed bracket, it wasn’t releasing properly.
Good luck!
Good luck!
Ambleton said:
I'd go for propshaft bearing mount/Bush (if there is one) my pal had it recently on his VW toureg.
95% of the time would drive fine until it hit a particular speed and the whole lot would go out and vibrate horrendously. Once off centre that's it, it stays there due to centrifugal force.
The bearing on the propshaft is in like a rubber donut/Bush that is in itself in a housing bolted to the car structure. It degrades over time and stops holding it centrally, manifesting itself in the above. Well known issue on touregs (and derivatives).
This. I had it on a Monaro. Once it had been annoyed it would reverberate until I stopped. It was filling removal levels of vibration.95% of the time would drive fine until it hit a particular speed and the whole lot would go out and vibrate horrendously. Once off centre that's it, it stays there due to centrifugal force.
The bearing on the propshaft is in like a rubber donut/Bush that is in itself in a housing bolted to the car structure. It degrades over time and stops holding it centrally, manifesting itself in the above. Well known issue on touregs (and derivatives).
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