Thread: Death Wobbles

I was chatting to a Range Rover owner who had similar trouble with his classic, he eventually took it to Peddars who diagnosed soft bushes and fixed the erratic steering problem completely.
It sounds like it may be time to get Peddars to have a look and measure.....


Ian
Bittern

If you have a look on the patrol 4x4 forum it goes into great detail about the death wobbles.
Replace your radius arm bushes and the panhard rod bushes (uerthane) check the caster settings. You may need to slot the swivel housings to get it correct.

As a former GQ owner, I can assure you the bushes are 90% of the problem on a GQ.....

Extremely important to get a Wheel alignment after also.

But:
Since you've swapped a GQ front into RRC, and you've also changed diff pinion angle and caster, spring perch.... There are unknowns

Without seeing it and taking measurements, or having the details provided it would be difficult to ascertain if you have got something out of alignment or not.

Bottom line is that it's common as muck on GQ's and the urethane bushes fix it - on the GQ.... Slotting the swivels for the additional caster also req'd in some cases. e.g:
If you have a lift, then you must slot the swivels on a GQ to get the correct caster.

If you have a GQ housing in your RRC, and everything is to Rover spec (pinion angle, spring perch, swivels etc, then you'd be OK - so bushes are req'd.

If youre not offroading to the point where you need huge flex, then urethane bush in the radius arms should be OK, or use the 'holey' bush if you need the flex. These are regular routine replacements on GQ's - almost an annual affair.

Might also be worth looking at Superior's radius arms if you're having issues with clearances on the front bush / mount.

I had a classic some years ago with the same wobble. Turned out to to be the swivel pre-loads. I removed some shims to tighten them up. But you have patrol diffs....

Radius arm bushes are polyurethane, although they are about 2 years old and I punish the car so I dare say they need doing. Panhard bushes are polyurethane. My caster angle is 3.5 degrees, Patrol spec. As I mentioned, I did have the pinion angle parallel with the transfer case originally, but that gave me too much caster and no turning circle so I reset it to Patrol spec thinking that may help my issue. The swivel hubs have the correct preload. The only things I haven't replaced in a while are shocks and steering damper, they are 4 years old. The wobbles started about 12 months after I did the conversion. I found a broken bracket on the diff so it was effectively only held in by 3 bolts on the radius arms.



This is my flex.

Is your steering damper a return to centre type or plain damper?

Sorry for the late reply. It's a standard one. Don't like RTC's used to run them on mine vehicles and the springs continually broke.

I have ordered a new radius arm bush kit, new shocks and damper. We'll see how they go.

Some p-troll owners had issues with RTC dampers and death wobbles. If anything the failing RTC damper exacerbated the wobble - right at about 80km which is not pleasant.

I've heard of RRC and defender owners complain of similar damper-related issues (non-rtc types as well- bilstein comes to mind) - however usually accompanied by bigger lifts (3-4") and larger tyres.

In some cases a new damper made the problem worse - occasionally the damper is not fitted correctly (especially on the hardened aftermarket track rods with the adjustable brackets).

Plenty of fun to be had changing out those radius arm bushes. Hopefully the new bits resolve your issue

My mounts are custom anyway as I had to weld the RRC damper mounts to the Patrol track rod. From memory, I think I have the other end mounted to the panhard, the RRC factory mount is the diff. I might have to fabricate something....

I have polyurethane radius bushes already, easy peasy to change

I might ask this in this thread as well. The angles on my rear A frame and trailing arms are the wrong way I believe. I am experiencing too much "squat" in the rear, especially when climbing. After researching a front 3 link conversion, I have concluded that my A frame mount needs to be higher on the diff so that the A frame is closer to horizontal than the trailing arms. Currently, my instant centre is way above and in front of the car, if I move the A frame diff mount higher, I can bring it back and down about where it should be. This would explain why I lose front traction pointing uphill. Every time I get the front wheels up on a ledge, all the car wants to do is tuck the rear. All this suspension wizardry is starting to make sense lol. So does this sound right?