Outer Limits 4x4 Board

Not a lot of modified 4by specialists down here in southern Tas so any ideas appreciated.
Have a gu running a6 inch lift with 15mm spacers and 35mtrs ,7degree caster plates and cannot get the shake out of the steering even at slow speed eg 40kmplus
seems to set up by the slightest deviation in road surface.I know the gq and gu were common for it but this seems excessiveas there is no movement in steering components.
Possibly a caster problem?

U need some radius arm drop brackets. Using a lift that high causes wobbles for the radius arms as they are no longer holding the diffs stable.

do a search on 'bigred' he uses them and has no dramas at all - i believe they are sourced from 'Wizard Performance'

TOM

you can get them to drive properly without the drop boxs.

How much castor do you have?

What is your toe-in/toe-out?

Radius arm bushes ok? Panhard bushes in good condition?

M&M Custom Engineering wrote:you can get them to drive properly without the drop boxs.

How much castor do you have?

What is your toe-in/toe-out?

Radius arm bushes ok? Panhard bushes in good condition?

this is all true. the radius arms have nothing to do with your problem. the problem is caused by the panhard being less effective because of the angle it is on, 6" lift puts it right on the edge of being useless. I think the reason the radius arm box things get rid of it alot of the time is that they bring the castor back to where it should be which actually brings the panhard mount on the axle up an inch or something(just slightly back into the plane of usefullness), because it rotates up as the castor increases. try running a little bit more toe-out and a bit more preload on the knuckle bearings...

Slighly off the subject, but you GU wouldn't be a goldy colour and have custom tube rear bumper ends would it?

i stand corrected.

JMO but...
Toe out is only a cover up. And not a real good one at that. It makes ya tires make more noise and also prolly wear quicker also. It does seem to help though.

Maybe should look at mounting points on the panhard? I have seen a couple of nissans with modified panhard mounts.
Is this hard to do?
I reckon you could prolly move the lower mount up a bit without too much drama.....??? (getting ready for a roasted fatass )

I think bushes etc on a lifted rig get neglected a bit also, as they come in for a lot more wear and should be replaced more often than a standard setup.
Same with all the other threads on this topic. Check everything as far as alignment/tyre balance bushes etc. Then if shimmy still there, look at modifying your shit to suit the lift.

Your wheel spacers will be making things a lot worse also!!!!
I have heard that some castor plates are not what they should be either so to speak. Make sure you get your castor checked cause if you have too much this will be a major part of your problem. It is very possible to have too much positive castor!!!!!!!

Yeh it is gold with custom bumper ends.
Have had the problem for about 18+months and does give me the shits on a long trip but does keep me awake.
Have had several wheel balances,replaced pivot bearings,steering damper,panard bushes toe in checked but not caster,even tried 33"ats and all have made little difference.
Cant see how panard angle would cause shimmy but am open to any ideas and all taken on board.

Thanks

If you've tried everything, give Wizard performance a call - he runs 8 inch coil lifted patrol and he'd know what you're talkin about and the remedy for it.

TOM

GARS wrote:Yeh it is gold with custom bumper ends.
Have had the problem for about 18+months and does give me the shits on a long trip but does keep me awake.
Have had several wheel balances,replaced pivot bearings,steering damper,panard bushes toe in checked but not caster,even tried 33"ats and all have made little difference.
Cant see how panard angle would cause shimmy but am open to any ideas and all taken on board.

Thanks

Try adjusting the tie rod to give about 5mm of toe out. Try it. You will have to play around a little to get a figure that it drives well on.

Check the castor, it should be about 1 to 1.5 degrees, excessive castor can cause some shimmy.

i had 5 1/2 degree caster plates and it used to wobble until i changed to drop brackets.
with them i lost all trace of the wobble ...even if i set the ranchos to the softest setting and hit my favorite wobble inducing rough spot.

But at the moment i have a huge wobble from 40 to 95 kmh ...i thought it was from the unbalanced 36 swampers on 40 mm offset beadlocks so i fitted the 38 sort of balanced swampers on 10" rims back on yesterday which has improved it heaps but it is still there at about 60kmh.
havent had time to check it out properly but i noticed the rearest radius arm bushes have ripped the steel insert from the rubber and one radius arm is bent.
had a quick check of the wheel bearings and they seem ok and cant see much movement in the steering arms etc.
Up to now its done about 50,000 kms with no wobbles so i am presuming its something that's worn out which is causing the wobbles [and its getting worse]
shane www.bigred4x4.com

Mine is the same!!!
Got wizards drop boxes on the front control arms and when I first got the truck didn't seem to have it. But the more I drive it the more I notice it only at certain speed and then goes away. Seemed to be there after I flexed the truck up on the ramp the other day.

From the look of some of the rear bushes I think this may be the problem.
Will have to get em all replaced and see how I go.
Yet to get my new wheels and tyres checked for balance and a wheel alignment yet too!

The Pro Comp GU now runs air bags front and rear. Pretty standard radius arm set up - just castor bushes. At full height it's about 8-9". Guess what - no wobbles, just nose bleeds and a rock hard ride (and some drive shaft vibration). Effort was made to get front radius arms pointing dead forward through adjusting the panhard rods. Agreed, panhard angles need to be as close to flat as possible (still to do). Would be cool if we could adjust the panhard length from in the cab. An even more wild idea would be in cab adjustment to keep panhards level. We get more wobble in the ass from panhard shift on major wheel travel and hope that a 4 pt triangulated rear end will solve this. Anyone done this yet? Need ideas...

Hobzee (Locky left his machine on)

LOCKY wrote: We get more wobble in the ass from panhard shift on major wheel travel and hope that a 4 pt triangulated rear end will solve this. Anyone done this yet? Need ideas...

Hobzee (Locky left his machine on)

yep. works well.

LOCKY wrote:The Pro Comp GU now runs air bags front and rear. Pretty standard radius arm set up - just castor bushes. At full height it's about 8-9". Guess what - no wobbles, just nose bleeds and a rock hard ride (and some drive shaft vibration). Effort was made to get front radius arms pointing dead forward through adjusting the panhard rods. Agreed, panhard angles need to be as close to flat as possible (still to do). Would be cool if we could adjust the panhard length from in the cab. An even more wild idea would be in cab adjustment to keep panhards level. We get more wobble in the ass from panhard shift on major wheel travel and hope that a 4 pt triangulated rear end will solve this. Anyone done this yet? Need ideas...

Hobzee (Locky left his machine on)

Some pictures of this would be sweet...............please.......for us all......

just goin through the old the old threads.

i have a gq x cab with a 7" lift 5 link, rancho etc..

your panhard rod is the cause. drop the top mount down about 90mm, or until the draglink and the panhard are parallel.

when you go over a bump the two rods go up. as they are not the same length or have the same pivot axis the lengths change by different amounts. hence your wheels steer slghtly, or wobble.

by making them parallel again, when they are in their normal range of on road movement their lenghts will change very little with respect to each other.

castor has an effect on wether you will get a wobble or a shimmy. also set your swivel hubs to 15lbs, and drop your tyre pressures on road to stop tour tyres bouncing, hence causing the wheels to raise and fall harmonically causing wobble.


cheers mate

bru

Hi guys, I'm having the same problem. I'm running 5inch lift on 315/75R16. I tought it is the dumper so replaced it with RTC one but it got worse and had to put the old one back. It usually does it around 70 - 80km/h. I took the car to Mannell motors. Since then I had replaced front wheel bearings, adjusted steering box, changed panhard rod bushes, wheel aligment and now I'm waiting already for 4 weeks for new after market steering arm. Forget to mension, after all that the shimming just got worse and I'm scared to go anywhere near highway.
Jerry

TYRE balance...........

Bazzle

bazzle wrote:TYRE balance...........

Bazzle

Baz is this your rec to the last as I am having some dramas as well it is more prominant at 80-90 but you can still get feed back through the wheel at higher speeds.

I do mash alot of gutters though taking advantage of the capability in an urban environment.

as i said before, i had a bad wobble problem.
Had an alignment done after i bent the tie rod straight and found a few problems.
replaced the radius arms ...better.
replaced the trailing arm bushes with nissan rubber/johnny joints...no change.
replaced the steering arm with an adjustable one, replaced panhard bushes...all good again

i couldn't see any movement in the steering arm balljoints and panhard rod bushes when i tried it by myself but its now fixed so some tiny movement in one of these was the main problem .

hope that helps....shane

big red wrote:as i said before, i had a bad wobble problem.
Had an alignment done after i bent the tie rod straight and found a few problems.
replaced the radius arms ...better.
replaced the trailing arm bushes with nissan rubber/johnny joints...no change.
replaced the steering arm with an adjustable one, replaced panhard bushes...all good again

i couldn't see any movement in the steering arm balljoints and panhard rod bushes when i tried it by myself but its now fixed so some tiny movement in one of these was the main problem .

hope that helps....shane

Shane I think I have worked it out now after getting under the truck for a look. I can't see any bush fatigue anywhere except maybe a little in the the swaybar bushes and I think that is mainly the way they are loaded up at a slithly different angle.

I can remember now hearing a bit of a bang on the left side coming out of home one morning thought it was just a rock from the MTR's but it was a bit of a crack which is why I remember it and thought it was unusual. However I noticed there is a balancing wieght on the inside of the left front wheel and I think I might of thrown one of them that day as there looks to be a wear mark from a missing one cannot be positive as it has been balanced a few times.

Seems the wobble is actually left side biased so I might try that first.

hi all my disco sufferrs the same prob and i am sure it is the panhard rod and also the castor this gq conversion has been a pain in the arse other than a bit of wobble (only at low speeds on rough road) it goes good till the front shaft started binding

Hi guys

Grave dig i now but have the same problem and have some questions.

In what order would you start replacing / looking at things if you had your time again ?

Just bought a GQ and am now broke so don't want to rush out without a bit of direction.

It has a wobble at 80kmh but gets really bad when go through a bend.

On the straight its bearable but once you start turning the wheel you start hoping your wearing brown undies !

Any help would be greatly appreciated, Cheers and Thanks.

Nick

CWBYUP wrote:Hi guys

Grave dig i now but have the same problem and have some questions.

In what order would you start replacing / looking at things if you had your time again ?

Just bought a GQ and am now broke so don't want to rush out without a bit of direction.

It has a wobble at 80kmh but gets really bad when go through a bend.

On the straight its bearable but once you start turning the wheel you start hoping your wearing brown undies !

Any help would be greatly appreciated, Cheers and Thanks.

Nick

mine does the same at 80k, not 75 not 85 but only 80k.
its not as bad tho. i usually have it the worse when i hit a pothole at that speed and it shaves the wheel a bit.
id like to know how to get rid of it, its not bad just anoying.
ive already replaced bushes etc...
next step im thinking is wheel balance and alignment (although ive had it done not that long ago)
if it still does it after that then i dont know what else to do

My biggest problem is that it is one std suspension.

Its got me stuffed.

I have a similar problem with mine.....4" lift, castor plates, got the 33's balanced and still wobbles.......put my All terrains back on and its gone. Not sure if i have a buckled rim but it only vibrates with the bf's on.

Jimbo wrote:I have a similar problem with mine.....4" lift, castor plates, got the 33's balanced and still wobbles.......put my All terrains back on and its gone. Not sure if i have a buckled rim but it only vibrates with the bf's on.

Thanks jimbo i'll change the rims around and see how i go.

Cheers Nick

Hey everyone, Thought i'd throw my 2 bob in. Got my 6" lift put in by Cris in Cuboolture qld. Did a sweet job. I'm from Newcastle N.S.W. Drove from Caboolture to Fraser on no name brand tyres straight after the lift was put in. It was a nightmare. Came back complaining like an idiot. Cris, out of his own time put in a new set of Genuine front arm bushes (Didn't have to but he did). Helped the problem heaps. Still had problems driving back down to N.S.W. though but a whole lot better. Finally, a month later got Cooper STTs 35" with new rims put on. Heaps better again. I only got 15" rims put on and I get them balanced every 20 thou. I got the coopers because i heard another major brand I was going to get were hard to rebalance. Problem i have is i keep finding Leds from the inner of the right wheel on my driveway (they warned me the 15" rims will be too small, my problem). Going back to basics, Get to know you leds, make sure their are no rocks, nails, mud e.t.c. in your treads. Little things like that can cause big problems. My opinion is use genuine Bushes. Your problem may be way past all this, but it's a start. From what i've read, their is no definate answer but we might aswell start with the cheap basics. Without advertising too much, Good on ya Cris, Great job! (met cris via this site, not related or anything)