Thread: lacking 'peddergree'!

So for a few months or so, I've had this annoying 'death wobble' that's not a real death wobble in the D1.
Had a case of it before, changed all the bushes that previous experience with the RRC had taught me to look out for.
Got the first case of it sorted with the change in drag link tie rod ends.

That was about a year or so ago, been fine ever since until a couple of months ago when it kind'a returned.
Problem was the death wobble occurences were hit and miss, till it one day clicked under what conditions it happened(precisely).
Once I'd figured it out, I could at least drive around the problem.

So conditions were: driving above 80k/h power on(mattered not how much or little accel was used) hit a metal join in the road(basically every hundred or so meters on the notorious western ring road here in Melb), D1 got the death wobbles. (violent shaking of steering side to side)
Getting them to cease was more hit and miss too, the only way to quickly stop it was to slow down(eg. 10k/h) then speed up again(say back to 80) .. otherwise slowing down to below 60k/h was the only other way to stop the shaking.

60k/h on the Western Ring road will almost certainly see you rear ended, because it's imperative that a minimum of 249k/h is maintained, lest you aggravate the idiot behind you, or risk them entering into your bootspace!
Seriously! .. worst road in all of Aus in terms of driver aggression.

Anyhow, so those were the specific conditions by which my D1 would death wobble it's way to work or back home.
Recently I had been taking son into the eastern suburbs for his work experience, along another freeway, sitting 'tentatively' at 100k/h .. but because this freeway has none of these metal joins .. no death wobbles.

Quick history on the death wobbles in it's initial bout .. I did change the steering damper, which was about my third guess as to what was causing it. (1. panhard rod bushes/bolts, 2. shocker bushes, 3. steering damper, 4th(and fixed) were the tie rod ends)
In addition to this, I also changed the steering damper bushes, as they got chopped out due to an oil leak.
So last weekend I did the swivel preloads, and also triple checked bearings again for slackness, and re tensioned.
Having done that, death wobbles got (slightly)worse!

Pulled radius arms to check bushes .. all nice and tight, I'm thinking a previous owner may have already changed them not long before I got the D1, but now I've put 50K klms on it.
The bolts had the same clearance as a new bolt had, so old bolts re used(new ones kept for another time).

So there was the only thing left to check, just in case, which I'd already checked and confirmed to feel like it's fine .. and that was the steering damper.
And this is the steering damper I changed about 18months ago(30K klms)
When I did it's bushes, it was tested(by hand) and felt smooth and tight in it's operation, basically like a new damper does.
But, for the sake of $50 I just bought a std steering damper(Armstrong) because I had no other option to work with.
The steering itself is nice and tight, no slack, no backlash, no kicks except what I remember as normal for a D1/RRC when working fine.

Just this death wobble under the specific conditions, stated above.
Note that if I hit those metal joins in the road with no throttle, no death wobbles!, it was only under power, and I kind'a had the thought maybe a CV or axle, or some front drive train anomaly due to the power on/power off change in behaviour.
But what on earth could be causing death wobbles in the actual drive train?

Anyhow, damper removed, fitted the new std steering damper and tis all perfectly sorted now! (spuriously tested at a speed a bit above the legal limit, and about 33% more than my preferred rate of progress).

So, to the company lacking in Peddergree, and full of BULL(contrary to their TV ads claims!) ... up yours!

Originally Posted by donh54

....
The other was the rear radius arm bush where it goes through the chassis - neoprene were terrible, genuine were a big improvement. YMMV

I had the polar opposite experience in my RRC with 'plastic'(urethane) bushings.
I did over 550K klms in that RRC over about 10 years(but had it for 20 years).
Seemed like every other month I'd be changing a bush somewhere, whether it was radius(real PITA) or trailing arm-chassis <triangle> bush or panhard bushes(which was usually the bolts/inner sleeve joint wearing out).

But I don't think I went through more than 2 steering dampers. I do remember one Koni that I did, and then one original(Armstrong). If I did more than those two, I can't remember.
But over a short period of time, I changed all the main bushings on my '79RRC to Nolathanes and couldn't have been happier. Had to retire the RRC due to major floor rust(and cost of petrol) but I'd done well over 200K klms on those Nolathanes and never had any of them feel loose at the time of letting it go.

Speaking of bushes, when I finally stopped using standard Landrover trailing arm chassis end bushes and firstly the modified bush that Rangie Spares(now Les Richmond Auto) version with the dished rubber design, the major improvement it gave was a total elimination of bump steer from the back end on really rough tracks. Genuine would only last a few thousand klms before they would start bump steering the back end. Same with the Nolathanes(eventually) where they just lasted what seemed forever on that main chassis bush.

My plan over the near future is to change the major bushes with plastic on my D1(simply due to the experience I had on my RRC).
But when I removed the radius arms, I noted that on (at least my) D1, LR have changed the design from the original RRC type.
With the RRC type, there was the normal two sleeve design, one outer that is pressed into the arms, and the one inner where the bolt pivots, so a large donut of rubber between the two sleeves
The D1 design is more of a 3 sleeve design tho. That is the two normal sleeves, but between the two main sleeves now is another metal ring separating the rubber into two sections rather than the one larger piece of rubber as per the RRC bush.

I'm wondering if this has something to do with the comments I'm reading where many folks are happier with genuine LR bushes now, whereas my experience with the RRC was that they were the worst(in terms of longevity).

With tyre pressures, when I had my first bout of wobbles, I thought to try lower tyre pressures, normally run at about 33-35psi, so tried 26psi and what was occasional wobbles became savage full time wobbles over 60k/h. so much that I had to U turn and go back and try more pressure, and went to 30psi. still worse, so back to about 36 where it then went back to occasional wobbles again.
This second time around tho, tyre pressure made zero difference. ATM I'm running 33 all round and it feels (almost) comfy. Maybe a bit high as I'm seeing more tyre wear in the centre of the tread, so may drop down to 30psi for a while now.