Thread: 98 110 violent front end shake - harmonic

We have had the same happen with slack in the panhard rod. Just every now and then we got the 'death wobbles'.

This was quite frustrating as we were on holidays in the NT at the time and I had 2 separate wheel alignments from different tyre joints and they didn't pick it up.

Once the bolts on the panhard rod were tightened (VERY tight) no further problems until we got back home and replaced the bushes as well.

BTW crook tie rod ends and worn / out of round tyres can display the same symptoms




Erich

the alignment bloke does know they are supposed to have TOE OUT , right , not toe in like most tyre services set them at

sometimes even if you have good panhard bushes there will be some clearance between the bolt and the inner bush sleeve, wrapping a shim around the bolt will help (eg a strip of beer can )

I am having the same problem at the moment , mine seems to be the panhard rod bushes , can't find one's locally that will last very long at all .

Originally Posted by uninformed

I can only go by what the WSM told me. New bearings are NSK, old ones were Timken (and seemed fine). I checked the preload with a trigger pull gauge (rifle) over and over and got a consistant reading in the mid range of LR specs. One side used exactly the same shim stack as previous, the other only needed a slight adjustment)

I can check again, it just means removing the: wheels, brakes, drag link and track bar (I think?)

Bear in mind Landrover specs are without seal, CV and any other associated components in place.

As copied from Workshop Manual

Check and adjust preload on bearings
NOTE: Swivel housing oil seal and axle
should not be fitted.
47. Attach a spring balance to ball joint bore and pull
balance to determine effort required to turn
swivel pin housing.
Resistance, once initial inertia has been
overcome, should be 1.16 to 1.46 kg. Adjust by
removing or adding shims to top swivel pin.
48. When setting is correct remove top swivel bolts,
apply Loctite 270 or equivalent. Refit bolts and
tighten to 78 Nm (58 lbf/ft), and bend over lock
tabs.

How much difference it makes I couldn't say, but guess it would make a diffence

I had a 1983 Range Rover from new and did 750k kilometers in it. It developed this same alarming problem from time to time.
I found it to be a combination of things as front suspension items wore.
Steering damper
shock absorbers
radius arm bushes
panhard rod bushes
swivel axle bearings
ball joints
I found that the steering damper was always the worst contributing factor. I found either Koni or Bilstein to be the best replacement.
Steering dampers were deceptive in that they seemed effective through most of their travel, when in fact they act in a limited travel region for most of the time. (ie with the steering straight ahead) That area deteriorates and the damper is scrap while appearing to be okay through the rest of its travel.
It was always necessary to ensure that the rubbers of dampers and shock absorbers were in good condition and bushes of radius arms and panhard rod the same.
I would start looking to find your problem by purchasing and fitting a new Koni or Bilstein damper first. And then working through the other items in the order I've listed them. Those quality dampers are expensive. If a new damper doesn't solve the problem immediately, then keep it for a spare until it is needed, and work through the other items one at a time.
Very disconcerting problem and I hope you eliminate it quickly.

My money is on the pre-load on the swivels...

M

The steering damper will, at best, mask the underlying problem - it is intended to protect from large movements such as where one wheel hits a pothole rather than as a shimmy dampener.

It is very likely that there is not a single problem, but an accumulation of minor problems, including all the ones suggested above. In my experience, if you want to find a single cause it is most likely to be swivel preload (and note the comment about being measured without the seal), followed by panhard rod bushes, wheel balance, oversize tyres and tierod ends.

John

Originally Posted by uninformed

Hey all,

I was heading up to Toowoomba from the Gold Coast. At Plainland (just before the Home Hardware) I drove over a very small step down in road surface. Think something along the lines of a resurface and where they blend the new and existing. So quite a small step down straight across my lane. I was doing 95-100, maintaing speed (i.e. not braking, not decelerating or accelerating) Slight decline in road and nice straight road. This step down minor and considering the amount of road works, pot holes and defects from Ipswich to Toowomba, very minor.

Well the front end started an immediate shake that came through the steering wheel and nearly shook me to death. I mean I could feel my brain bouncing in my skull. Very, VERY disconcerting. This was so bad I could barely hold the wheel with both hands and try to keep some sort of line, which was for the shoulder and into a short turing lane. It did not stop until I got down to about 30km or less.

I pulled up in this side road and looked over the vehicle. I am surprised it did not tear the 110 apart it was that bad. Everything seemed ok???

I have had similar happen once before, at 80km/h on the end of Bermuda St about to go onto the MWY at Burleigh. I was on a slight up hill, left hand bend and decelerating. I put it down to a fluke in combination with the crappy concrete road surface that puts my 110 into a pitchy harmonic of front and rear suspension.

This time was worse and pretty ok road all things considered.

I had just done a tyre rotation.

A month ago, I overhauled the front axle: new wheel bearings, swivel bearings etc.

Last week I had my mate check the wheel alignment: Castor is at -0.5 degree. each side is within 0.25 degree of each other. Toe was spot on according to him.

New OEM steering box in the last 12 months with new panhard bushes. I took care in getting all things correct as per manual (steering box centred etc) It drove spot on.

I could possibly have a very small shimmy at 100km/h, but it is VERY small if it is there?

The steering, post event, is now trying to veer right, steering wheel seems off centre. Im guessing steering dampener???

Steering dampener is 5 years old or so, Bilstein.

Wheel bearings feel good. Hubs are not hot at all.

Drag link and track rod are Maxidrive.

What to look for...I do not want to die or kill someone!!!!

In the uk we call it Death Wobble. And if you have had it happen then you know why it is called Death Wobble. Happens at speed when you got a hit a break in the road or seems on bridges.

Caused by the front swivel bearings

Take out the shims on the top pin of the swivel, until you have the right load on the swivel. this will work for the time being but need to replace the top and bottom bearings on the swivels.