Violent Shuddering at speed

Hi

I have had this problem for about 6 months now and haven't posted about it.

When the car hits a pothole or even relatively small bump at speed, the car explodes into a violent shudder, things fly around the cabin, i have to brake and come off the motorway. This is needless to say both alarming and dangerous.

So far:

New drag link and ball joint assembly
Steering Damper
Suspension Ball joints top and bottom
Full alignment by a good firm
Tyres are good and at correct pressures and balanced
Airbags and shocks about 18 months old
Discs and Calipers new
Radius Arm bushes (original Land Rover)
Rear prop shaft and front UJ's

I will check the Panhard bushes but my garage tells me everything is very tight

I have been on various forums a this seems to be problem with this car but with no definitive answer.......

I have had various Range rovers, Discoveries and defenders but never experienced anything as severe as this.......

If anyone has any pointers as I am now at my wits end, it seems as if something big and heavy (like a whole axle) is either loose or out of alignment.

Many thanks and I have had a good search but as I mentioned nothing definitive.

Ash

Steering box?

Chassis to body mounts??

Spiggy, thanks but not that

Saint........ Ah, very possibly as that's how bad it feels......how on earth do i check those??

When you replaced the radius arm bushes did you replace the bolts and torque to spec? Checked wheel bearings and swivel pin pretension?

Have you crawled underneath the beast while having someone turn the steering wheel. looking for play or movement in the system?

Swap the wheels front to back and see if it makes a difference, some tyre faults cannot be seen.

Datatek said:

Swap the wheels front to back and see if it makes a difference, some tyre faults cannot be seen.

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+1 ive seen plenty of dangerous wheels/tyres its amazing how many fools will fit/repair/supply/sell a defective tyre(s)/wheel(s) for a quick buck

WSR, I didn't do the RA bushes but the guys who did know what they're doing and yes I asked them about Preload on the ball joints so can't seeing being that

Keith, this is so severe that I just can't see it being a tyre fault and the tyres were o the car for may miles without a problem, I am leaning toward what Saint said about body chassis bushes, it's as if the whole car is gonna blow up and it is initiated by a bump.......very scary

Thanks guys

wil2813 said:

+1 ive seen plenty of dangerous wheels/tyres its amazing how many fools will fit/repair/supply/sell a defective tyre(s)/wheel(s) for a quick buck

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The only thing about that is as I've mentioned I have been on these tyres without issue for many motorway miles, it is honestly so severe, I know these are big lumps of rubber but I just can't envisage it

A couple of questions.. is the vibration transmitted through the steering wheel ?

When you say the whole car shudders and you have to come off the motorway does it settle down when dropping below a speed or do you have to stop and then restart ?

Hi Adam

No it doesn't come through the steering wheel, it is a definite up and down motion

All a bit overwhelming but from memory I pull on to the hard shoulder and slow almost to a stop to halt the shaking, not quite a full stop but I'm guessing about 20-10mph.

Braking does not stop the shuddering it is speed related

Seems like a harmonic issue

I trust you still have your harmonic dampers fitted to the diff casings?

AP90 said:

WSR, I didn't do the RA bushes but the guys who did know what they're doing and yes I asked them about Preload on the ball joints so can't seeing being that

Keith, this is so severe that I just can't see it being a tyre fault and the tyres were o the car for may miles without a problem, I am leaning toward what Saint said about body chassis bushes, it's as if the whole car is gonna blow up and it is initiated by a bump.......very scary

Thanks guys

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Tyres fail, cords let go, half an hours work to swap front to back to eliminate the possibility.

Datatek said:

Tyres fail, cords let go, half an hours work to swap front to back to eliminate the possibility.

Click to expand...

I've got some spare wheels here if he want to pop up and swap them over for a test-drive.

Grrrrrr said:

I've got some spare wheels here if he want to pop up and swap them over for a test-drive.

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Thanks very much, but I had a bit of a fiddle this afternoon and on Keith's suggestion I swapped the fronts and rears, unfortunately scary shudder still there (took it up the M1 to J5), couldn't be arsed to climb underneath to check the panhard bushes after hauling the wheels around, taking it to the garage tomorrow to get the bastard up on a lift, I'll get the guys to check the body to chassis mount as Saint suggested.

I've been so good to this car and all it's done is kick my arse.........

In fairness it has been pretty good all the issues have been easy fixes but this problem is a major and my garage and I can't find a solution........

Thanks everyone

im leaning away from tyres (though i think it's a valid point) as it happens when you hit a bump, a way to eliminate this would be to get the balancing checked a delaminated tyre would show for any half decent tyre balancer.

i'm also leaning away from the chassis to body mounts as the drive train and suspension is mounted to the chassis..

with the vibration in play even in slowing down and going with a near stop suggests something is being pushed out of alignment, panhard bushes would transmit through the steering wheel. It does seem like as you an axle is moving out of alignment.. have you checked that ? the other thing possibly is a severely worn wheel bearing, which would in effect act like the axle is out of alignment ! have you checked the UJ's again - have they been fitted properly ?

A very long time ago, I had a car (DX Vauxhall) that developed a death wobble after hitting a bump at more or less any speed, it only stopped when nearly at a halt. It was a duff shock absorber. May not be relevant but worth checking.

Thanks guys, well yes it may be shocks as it has non standard Terrafirmas which in my opinion aren't great.......

The only other clue, is when the guys did the ball joints, for couple of weeks the problem seemed to be cured, but maybe I didn't hit a big enough bump....

Adam how do I check that the axle is moving out of alignment as this seems the most feasible explanation as it does take a lot of weight to shake a big car in this fashion and the axle would do that also you haven't got a 993 have you?

AP90 said:

Thanks guys, well yes it may be shocks as it has non standard Terrafirmas which in my opinion aren't great.......

The only other clue, is when the guys did the ball joints, for couple of weeks the problem seemed to be cured, but maybe I didn't hit a big enough bump....

Adam how do I check that the axle is moving out of alignment as this seems the most feasible explanation as it does take a lot of weight to shake a big car in this fashion and the axle would do that also you haven't got a 993 have you?

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I would check the torque on the bolts. to be honest for an exle to be loose and cause vibration there would have to be a lot of movement for a vibration and that would result in a clonking noise at low speed over bumps. i think keith's point on tyres is valid, get them balanced and checked first. i'd also check the UJ's to make sure they were fitted, as saint said.. check the harmonic dampers as well..

As a question for all out there.. would a worn diff cause vibration at speed.. i would think so as its only when the road speed gets high that the vibration occurs, this would preclude a gearbox or engine issue as it would occur at low speed higher revs. ergo a worn diff or bearing on the diff would reult in movement at speed resulting in a vibration. i may be wrong. perhaps someone with experience of overhauling a diff could give a viewpoint (WAMMERS!)

my thinking would be it has to be from the output shaft through to the road wheels or suspension

Is it on air or coil springs?