Thread: 98 110 violent front end shake - harmonic

Originally Posted by Reads90

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.

You are right, I have pulled the steering damper completely off and hasn't changed when the shimmy occurs at all.

Pulling the front balls down to get at the swivel pin bearings, I have found very slight marks in the cups where the rollers have been working, after washing the all grease out of the bearings so they completely dry of lubricant,
then rotating the bearing cone in the cup it's easy to feel the catch as the rollers pass over those marks.
.

As others have said, the prime suspect has to be swivel pin preload.
It is also very easy to check the panhard rod bushes.
Lie under the front of the vehicle and get a helper to turn the steering from side to side. You will easily spot the movement from worn bushes.

Originally Posted by djam1

Loose swivel pins??

+1,

Hmmm, it seems that everyone is quick to jump on the swivel bearing or pre load of.

Just to refresh, these have been replaced with new NSK in the last month. Pre load was set, checked and re checked as per LR WSM.

The similar "wobble O Death" was experienced in the last 12 months, prior to the front end overhaul (prior to swivel bearing change) The previous bearings being Timken and having been re set 5 years ago.

Now Im not saying it isnt them, but surely the above would rule it out somewhat.

What about the fact that it now almost feels like the steering dampener is more extended or pushing more? I say this because if nothing has moved link wise, the only thing to push the wheels to the right which would also make the steering wheel off centre in that direction is the steering dampener.

Yes the steering wheel and wheels are in alignment. That has not changed. Just now, if left to do its own thing on flat straight road, it wants to veer right. It did not before AFAIK.

It is possible that when the swivel pin preload was set one of the bearings had some dirt behind it that has now compressed or been squezzed out - this could cause preload tobe lost quite quickly. Pulling to one side (if not tyre pressure or dragging brakes or wheel bearings) just about has to be an axle alignment problem, usually due to worn or damaged bushes somewhere. Note that it could be the rear axle location, not just the front.

John

Why don't you just take the damper off and drive it to see if it wobbles...if your steering is set up right like you say you should easily be ale to drive without the damper.

It's also very easy to dismiss stuff because its NEW been caught in that trap before and ended up going back to that new component to find it was the issue all along, after spending unnecessary money.

I had front wheels/tyres checked for balance. One was 40g out but not horrible.

Driving after this did not make any noticeable difference.

Yesterday I changed the panhard rod bushes with new Super Pro units. The Old ones(stock replacements only 6-8 months old) looked fine as far as I could tell (nice and concentric and no cracks or deformed rubber)

Driving after this has made very little to no noticeable difference.

Today I removed the steering damper. It was a little bit oily on the main body, but could easily be coming from my slight blow by leak. Holding the damper vertical, with main body upper most, I compressed the entire length of stoke and let release under its own forces. Nice smooth operation in both directions, when I was applying the pressure down on it, it was even all the way. No dead spots or hard spots.

Driving with it off made the steering a little lighter as would be expected. It made no difference over all to what Im feeling in driving. Yes bumps were a little more noted, but that would be normal without it.

I will keep going through the list of things as I can, these will included:

shocks, radius arm axle end bushes, front propshaft and swivels.

Im still perplexed as why the steering is now settling (on straight flat road) to the right? The steering wheel and the road wheels are in alignment with each other.

Is the steering box 'centered' so that it has a preferential location? I have heard that such a thing exists but not sure if Landy boxes are like that or not. But if so, it may explain the slight pull to right on straight, flat road-the drop arm may be a spline out.