Thread: 98 110 violent front end shake - harmonic

The steering wheel now being mis-aligned is what I would be focussing on. Something is clearly not right with that! It really sounds like when you hit a bump, something moved. I'd have to say, I'm leaning towards something like a tie rod or steering related.... not so much suspension.


Regarding swivels:

My swivel pre-loads were very loose a while ago and the symptoms weren't "death wobbles" but large amounts of feedback from uneven road surfaces. EG. Potholes. A pothole would flick the steering wheel around briefly. But once the wheels were back on similar surface, there was no death wobbles. I would say vague steering though.

However, when you set the swivel pre-loads, did you do it as per the WSM with the hub assembly removed? Or with the hub on and only the wheel removed? There was a thread/debate on this a while ago, but my view is the weight/force you are looking for in setting the pre-load is very different depending on whether you check with the hub assembly on. I did mine with everything bolted on, except the wheel and I went for about 6kgs of force on spring scales. Curious to know how you did yours?

I had a very similar experience in the last fortnight. I've had a shimmy developing over the last few months and when I hit the highway this time it had turned into a constant shimmy (bit like out of balance tyres) from about 90-100kmh before smoothing out. Hit a mid corner bump of the right sort and the shimmy would turn into a death wobble only cured by slowing down.

Got to my destination and took it into the local tyre place. Once up on the hoist you could see the movement in the swivel hubs when working the wheel side to side. No movement top to bottom so the bearings were fine.

I removed three of the thinner shims on each side and it's pretty much fixed the issue, but I'll need to do it properly when I get home as it needs at least one more shim removed to be perfect and I need to check the pre-load.

These swivels had new everything (except housings) last year. They'd be lucky to have done 10,000 kms before they started to loosen up. When they were done they were rebuilt on the bench and set-up per LR specs with correct pre-load.

I suspect new housings might be needed at some point but I'll see how the re-adjustment goes.

My money is also on the swivel pre-load causing the issue described in this thread.

after a minor washout incident with the 110 last year it developed the same thing. Just about drove me insane finding it. new swivel overhaul, shocks, bushes, balances, alinements, lots of swearing was still there. The last thing I looked at was the panhard bushes. They were brand new a week bfore the incident and still looked good, but I put new polys in just the same, and bugger me no more wobbles! so simple!
cheers Scott

Steering box is only 6-8months old, brand new Adwest that came with pitman arm installed.

I followed the install procedure in the LR WSM, this included setting the steering box up to "centre". Once that was done, i installed the steering wheel in the straight ahead postion and aligned the wheels etc around that. The result was the best the car had been for years. Smooth, tracked great and steering wheel dead ahead for dead straight.

When I did the front end overhaul recently (new bearings through out etc) I set the pre load for the swivels as per LR WSM. That is, swivel ball and swivel housing mounted. No oil seals, no caliper, no hub etc. I used a trigger pull gauge (spring balance) to check the resistance as per LR specs and set it at the higher end as they were new bearings (NSK). The shim stack did not change on one side and only a tiny bit on the other. A mate told me all the good bearings are made to extremely close tollerances, in fact you should be able to get away with running a Timken cup in a NSK cone if same bearing part number.

I will still check the swivels for feel etc.

I checked my front prop shaft this arvo. Im not a certified prop shaft checker so could only just grab the unis and try and get movement in the joints etc. Seemed ok, maybe a little movement at the T/case end, but I think that is the T/case and not the D/C joint.

I dont think it the track rod or drag link. If the track rod has changed length that is only toe in or out. I cant see that causing the "going right" symptom. If the drag link changed length the wheels and steering wheel would be out of alignment. Both links are MD heavy duty so chances are they are still straight as the day they were sold.

What is the best way to check TREs?

Originally Posted by steane

........Got to my destination and took it into the local tyre place. Once up on the hoist you could see the movement in the swivel hubs when working the wheel side to side. No movement top to bottom so the bearings were fine.....

Can you explain a little more in what you did on the hoist and what bits your saw move in which direction etc?

I once had a similar steering shake (actually it was more of a savage weave) in my RRC. Couldn't figure it until I got underneath and got my wife to turn the steering from side to side. There was a massive amount of play in the panhard rod bushes. I fitted new poly bushes and haven't had a problem since. However, I see that you have addressed this issue.

When your car tends to veer right, does the amount of throttle that you're giving it affect the amount of veer? If the REAR axle bushes are worn on one side, then rear axle steer can produce this symptom. I had a series 2a that did this occasionally - brake and you went one way, power on and you went the other.


Another thought is that the front and rear axles may not be parallel. This could be checked by carefully measuring the distance between wheels on each side.

Seeing you have tried all the obvious like the Panhard rod bushes, let's put the thinking cap on and look at the not so obvious also.

One likely cause that can set the shimmy going is a incorrect caster angle of the swivel pins, do you have a moderate lift? and then with softer then usual aftermarket bushes, the whole axle could be working within the flex of those bushes

Next is the trailing arm bushes and the centre pivot on the back axle, are they firm also in their fitting? any slight movement there will cause the rear axle tracking to vary.

Looking next at the tyres themselves, you can have them balanced nicely, but so can a square object, are the tyres true around their circumference?

Are the wheels seating properly on the hubs? check for run-out ( using a dial-gauge indicator is a good way to do this ), this test will also show up any faulty bearings and one's that may not be seated properly as well.

I wonder if "angular resistance to rolling" is the correct term for this?

Check the angular resistance to rolling, jack the front up and tie a builders line around one of the wheels, do about half a dozen lap's around the outside of the tyre, with the hand brake holding the transmission still and with both front wheels off the ground and free to turn, pull the string steadily feeling for any catch or resistance to wheels spinning ( do the wheels on both sides in turn to make doubly sure ).
Anything that shows up here could mean that there is a fault in something like the front diff carrier or that one of CV joints might be damaged.

If there is a crook tyre that has part of it's wall flexing differently as the tyre rolls, that would be a tricky one to determine. Swap all the wheels with a known good set off another vehicle and try both vehicles, does the problem then occur on the other vehicle?

There you go, another check list to do and good luck!
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Originally Posted by uninformed

Can you explain a little more in what you did on the hoist and what bits your saw move in which direction etc?

Grabbed the wheel at roughly 3 oclock and 9 oclock and put a bit of effort into rocking it from side to side. In my case you could hear a slight clonk and could see movement around the swivel joint. Bit hard to rock the wheel and take a look at the same time, but you will feel it anyway.

I also noticed that the steering in my Defender became lighter as the swivels loosened up, and firmed up again when I took some shims out.