Shuddering at high speed I can't get to the bottom of...
Discussion
Hey all, I really need some help. Hoping one of you lovely people can give some suggestions!
Hyundai i40 tourer, 115k miles, has an uncomfortable wobble at higher speeds. It only becomes obvious when the car is properly hot, give it 30mins+ on the motorway and it develops.
Nothing through the steering wheel, mostly felt through the seat. Feels like the car has a side to side shudder. Can see the passenger side seat vibrating. More obvious when accelerating or braking. Same frequency regardless of what gear I'm in. Definitely rotational. Mpg has dropped around 10-15mpg since it developed.
Been to the garage 3 times. All 4 tyres replaced, wheels balanced, front alignment done, rear pads & discs replaced, front brakes are around 10k miles old.
Every time I'm told it's fixed but makes no difference (I think that's because the tech has a quick test drive, car isn't run for long enough, doesn't develop, they think it's fixed). I'm £850 in the hole already and no closer to finding the solution. 2 garages have said they can't find any issues with suspension, driveshafts, wheels
Any idea where to look next? Can't afford to keep chucking money at replacing parts that make no difference, but running out of obvious ideas that could be causing it!
Any suggestions would be really helpful. Cheers!
Hyundai i40 tourer, 115k miles, has an uncomfortable wobble at higher speeds. It only becomes obvious when the car is properly hot, give it 30mins+ on the motorway and it develops.
Nothing through the steering wheel, mostly felt through the seat. Feels like the car has a side to side shudder. Can see the passenger side seat vibrating. More obvious when accelerating or braking. Same frequency regardless of what gear I'm in. Definitely rotational. Mpg has dropped around 10-15mpg since it developed.
Been to the garage 3 times. All 4 tyres replaced, wheels balanced, front alignment done, rear pads & discs replaced, front brakes are around 10k miles old.
Every time I'm told it's fixed but makes no difference (I think that's because the tech has a quick test drive, car isn't run for long enough, doesn't develop, they think it's fixed). I'm £850 in the hole already and no closer to finding the solution. 2 garages have said they can't find any issues with suspension, driveshafts, wheels
Any idea where to look next? Can't afford to keep chucking money at replacing parts that make no difference, but running out of obvious ideas that could be causing it!
Any suggestions would be really helpful. Cheers!
olly.harris said:
Hyundai i40 tourer, 115k miles, has an uncomfortable wobble at higher speeds. It only becomes obvious when the car is properly hot, give it 30mins+ on the motorway and it develops.
Nothing through the steering wheel, mostly felt through the seat. Feels like the car has a side to side shudder. Can see the passenger side seat vibrating. More obvious when accelerating or braking. Same frequency regardless of what gear I'm in. Definitely rotational. Mpg has dropped around 10-15mpg since it developed.
Been to the garage 3 times. All 4 tyres replaced, wheels balanced, front alignment done, rear pads & discs replaced, front brakes are around 10k miles old.
Just thinking around your description to see if any of it helps narrow the issue down.Nothing through the steering wheel, mostly felt through the seat. Feels like the car has a side to side shudder. Can see the passenger side seat vibrating. More obvious when accelerating or braking. Same frequency regardless of what gear I'm in. Definitely rotational. Mpg has dropped around 10-15mpg since it developed.
Been to the garage 3 times. All 4 tyres replaced, wheels balanced, front alignment done, rear pads & discs replaced, front brakes are around 10k miles old.
If the issue were front wheels/hub/brake related you will generally feel it more through the steering wheel.
If the issue were rear wheels/hub/brake related you will generally feel it through the car.
If the issue were driveshaft/engine/gearbox related I would expect it more to be felt through the car more than the wheel.
So, while that doesn't give you an answer there are areas that may/may not be more likely from that.
I would be more likely to be looking at any driveshaft joints, engine mounts, rear wheel bearings, rear wheels for buckles, rear subframe bushings or similar.
On top of that, you need somewhere that will actually DIAGNOSE/WITNESS the issue rather than just swap random bits & charge you for it.
Loss of mpg plus vibration when hot would suggest a dragging brake somewhere to me. Possibly at the rear if you don’t feel it through the steering wheel.
Next time it happens, stop somewhere safe and try to find out if one brake disc is hotter than any of the others. Don’t burn your fingers!
Next time it happens, stop somewhere safe and try to find out if one brake disc is hotter than any of the others. Don’t burn your fingers!
stevieturbo said:
Then you need to be in the car with the person who might be fixing it, so you can show them the problem exactly when it is occuring.
It is pointless trying to fix something if they have never experienced the actual alleged problem
Sorry - for context the tech's have felt the issue before but put it on the ramp and can't find anything wrong with it. They changed the brakes as they found a distortion in a disc, alignment was out and tyres worn unevenly. When they take the car back out after the work, they can't feel the issue so assume it's fixed (because the cars not had a long run and it's fair to not expect a tech to do a 30 min motorway drive to test it) It is pointless trying to fix something if they have never experienced the actual alleged problem
There's been reasons for replacements thus far, but now I'm in the realms of things being replaced with no diagnosis as 2 garages can't find the fault.
littleredrooster said:
Loss of mpg plus vibration when hot would suggest a dragging brake somewhere to me. Possibly at the rear if you don t feel it through the steering wheel.
Next time it happens, stop somewhere safe and try to find out if one brake disc is hotter than any of the others. Don t burn your fingers!
Cheers for this - I've literally had the rear pads and discs replaced last week so I hope the garage would have seen if a rear brake was binding?Next time it happens, stop somewhere safe and try to find out if one brake disc is hotter than any of the others. Don t burn your fingers!
The sensation is a really weird one - when driving you can't feel the shuddering through the steering wheel at all, just through the floor, but you do feel it in the steering wheel when braking. Barely feel it till 50mph.
littleredrooster said:
Loss of mpg plus vibration when hot would suggest a dragging brake somewhere to me. Possibly at the rear if you don t feel it through the steering wheel.
Next time it happens, stop somewhere safe and try to find out if one brake disc is hotter than any of the others. Don t burn your fingers!
This, my thoughts are a seized caliper which only occurs when hot, either that or a wheel bearing which is overheating and causing similar symptoms.Next time it happens, stop somewhere safe and try to find out if one brake disc is hotter than any of the others. Don t burn your fingers!
Next time it occurs, stop and check all four wheels for temperature (you should be able to feel any large variation without touching the wheel - just hold your hand close to the centre). Or better - get hold of a laser thermometer, they're cheap off Amazon and will provide a more accurate reading.
nsa said:
The fact that your MPG gets worse leads me to agree with others that it's brake related. Caliper piston seizes when heated?
Top lurking, btw
Haha thanks, I've considered it a top skill Top lurking, btw
Thanks for the opinion. Driving the car again last night there's definitely no feedback through the steering wheel, even when braking - everything is through the seat and floor. So would point to rear brakes... Which is annoying considering a garage literally just charged me £300 to replace them last week.
Would they not have noticed something wrong at the time do you think?
I had a motorway speed vibration so was told to look at the wheel weightings, which seemed to help a bit but it persisted and after many things the control arm bushes got replaced which made a big difference too.
I know the frustration of seemingly done everything to stop a vibration and it still persisiting though!
I know the frustration of seemingly done everything to stop a vibration and it still persisiting though!
olly.harris said:
nsa said:
The fact that your MPG gets worse leads me to agree with others that it's brake related. Caliper piston seizes when heated?
Top lurking, btw
Haha thanks, I've considered it a top skill Top lurking, btw
Thanks for the opinion. Driving the car again last night there's definitely no feedback through the steering wheel, even when braking - everything is through the seat and floor. So would point to rear brakes... Which is annoying considering a garage literally just charged me £300 to replace them last week.
Would they not have noticed something wrong at the time do you think?
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