DEATH WOBBLE!!!!!!!!!!!

[hypo]

well if u havent read the trips and tracks section u woodnt know that i finally got my POS offroad 2day...(grinning from ear 2 ear still)

heres the prob:

after strengthenin my front housing i got it checked for straightness, the dude said it was straight as a die, cool i thought, but since building it up and putting it under the rig i notice that my front tyres sit like this \ /

ok looks bad but wen i drove it home from the turbo shop on friday night it was fine 2 drive a little bumpy coz it had no shocks in the front.

yesty i got some 1.5" wheel spacers 4 my b'day from my lovely girlfriend sarah, wen i put them on and went driving 2day i noticed the truck has a very deadly death wobble at about 50k's. but its not there all the time it mainly does it on nice smooooth roads and wen u r halfway round a bend, the only way 2 stop it is 2 JUMP on the brakes or change down a gear and gas it.

on the way home from driving i only pumped tyres back upto 20 PSI instead of the 30 that was in them b4 hand and it drove like a champ the wobble was there occasionaly but it was hardly even noticable...

how do i fix this ??? and i dont think it can b straight if the wheels sit like this \ /

opinions and solutions please ???????

i was thinking bout getting some of the adjustable kingpins but they r pretty exy

[hypo]

wen i got home i jacked the front up and spun the tyres on both side 2 c if the spacers wher out of round or something but they run true so i dunno wot 2 do.

BTW i have ifs hubs upfront with rotor spacers aswell as the wheel spacers but it was totally fine until i fitted the wheel spacers

also 4got 2 mention that the wobble is that bad it nearly is impossible 2 hang onto the steering wheel.

could it have anything 2 do witht the fact that my steering box is noe more vertical than b4 ?? (altho it was fine until the spacers r fitted)

[dumbdunce]

get your castor angle checked. with spacers, it might take a bit of fiddling to find a castor setting that works for you - for cruisers around 2 degrees is a good starting point, hilux axle is similar in construction so that might work.

the \---/ of your wheels is that a top view or a front view? if front view that's a bit strange, tne camber of those axles is pretty close to zero, I think maybe half or one degree, but have a close look at the bottom of the tyres, it is excessive toe in or out that is pulling the bottoms of the tyres around in funny directions? that can also cause nasty wobbles but more likely in a straight line.

I hate wobble diagnosis. start with a set of well balanced tyres that you know are round - pref from another vehicle that has no wobbles - even if you have to put 31's on.

[RUFF]

Have you driven it with the front springs you just fitted or is this the first time as well? If so remove the spacers and drive it again. If it still does it then its your Shackels flexing side to side.

[Area54]

Ben you are gonna find you have past the point of correcting this problem. Your camber is all out of whack, and you have IFS hubs, and 1.5 spacers, where is your pivot point in the tyre contact patch? about 3-4 inches (including average rim offset) OUTSIDE of the projected kingpin pivot point. You also have crossover, not a strong system if you have long shackles, flexy springs and no panhard. Due to the lateral strength of crossover, it will deflect the diff to one side (depending what steering lock you want). You only need a small road bump to start a harmonic vibe that will just keep going until you stop or slow down. You also had the 37's on right? Beadlocked? what is the distance between the wheel weight and the ground contact patch - kinda makes the weights ineffective. I wouldn't waste any money on trying to correct it - you might just have to live with it.

[Strange Rover]

Have you got the shocks back on it??

What about a steering dampener?

Sam

[Area54]

Have you got the shocks back on it??

What about a steering dampener?

Sam

additional steering dampening would be ineffective - the movement at the dampener mounts is far too small for it to be effective - most of the movement is about 15mm side to side at the tie rod, and this can be flexed in the mounting bushes.

[Wendle]

Ben you are gonna find you have past the point of correcting this problem. Your camber is all out of whack, and you have IFS hubs, and 1.5 spacers, where is your pivot point in the tyre contact patch? about 3-4 inches (including average rim offset) OUTSIDE of the projected kingpin pivot point. You also have crossover, not a strong system if you have long shackles, flexy springs and no panhard. Due to the lateral strength of crossover, it will deflect the diff to one side (depending what steering lock you want). You only need a small road bump to start a harmonic vibe that will just keep going until you stop or slow down. You also had the 37's on right? Beadlocked? what is the distance between the wheel weight and the ground contact patch - kinda makes the weights ineffective. I wouldn't waste any money on trying to correct it - you might just have to live with it.

what he said.

your tyre is loaded up at a point that is outside the angle of the vertical steering axis. So it takes very little persuasion to set up a harmonic oscillation or whatever the fuk it is called. Bringing the camber in to slightly negative will lessen it a lot, as you will load up the tyre closer to the centre of the vehicle.

Does sound like you warped your housing but.

[bazzle]

Sell the spacers or trade them for something safe.

bazzle

[V8Patrol]

1st job.....................go n get a front end check with and without the spacers... that will tell you where the angles may be wrong. TIP: use someone that specialises in 4x4s. Most car frontend specialists take one look at the kingpin set up and recon "thats it, must be right from the factory".

2nd job ...................re fit the shockers, and make sure that the steering dampner actually works.

3rd job................... PICS... of the "strengthing" you did to the diff, it may well have caused the problem in the first place. Also pics of the" \\ // " you are talking about. get a tape measure and measure the difference between top/bottom , or front/rear. ( I'd say the strengthing is under the diff not over ... am I right ?)

Questions....
1\ did they strip the diff to do the strengthing?
2\ did the tighten the bearings up properly if they stripped the diff?
3\ did they check what "straightness" was in the diff before they started the mods?
4\ is the strengthing fully welded or only intermentitly? IE welded 2", miss 2", weld 2", miss 2" and so on.
5\ where is it welded? along the top or on the sides of the diff tubes/housing?

[Guy]

I have had these excat symptoms with my Zuk .. I know serveal others that have had them as well .. I have found the most effectyive fix for mine has been get your tyres balanced .. I went throught the entire front end, kingpin bearings, swivel seals, wheel bearings, wheel alignment, steering damper etc etc problem "moved about" as to what speed it would occur.

Got the tyres balanced no more probs .. (until I knocked off one of the big banana sized bits of lead weighting .. same dramas return)

Perhaps the balancing covered up a bigger issue I am unsure, but thats what fixed or masked the problem for me...

[A1]

1st job.....................go n get a front end check with and without the spacers... that will tell you where the angles may be wrong. TIP: use someone that specialises in 4x4s. Most car frontend specialists take one look at the kingpin set up and recon "thats it, must be right from the factory".

2nd job ...................re fit the shockers, and make sure that the steering dampner actually works.

3rd job................... PICS... of the "strengthing" you did to the diff, it may well have caused the problem in the first place. Also pics of the" \\ // " you are talking about. get a tape measure and measure the difference between top/bottom , or front/rear. ( I'd say the strengthing is under the diff not over ... am I right ?)

Questions....
1\ did they strip the diff to do the strengthing?
2\ did the tighten the bearings up properly if they stripped the diff?
3\ did they check what "straightness" was in the diff before they started the mods?
4\ is the strengthing fully welded or only intermentitly? IE welded 2", miss 2", weld 2", miss 2" and so on.
5\ where is it welded? along the top or on the sides of the diff tubes/housing?

kind of answers
1/ Ben stripped the diff
2/ he rebuilt it
3/ yes he had checked b4 hand ,and it was straight.....
4/ he welded it 2" on 2" off
5/ the diff was welded in lots a places ...... but was checked again after all weldin was completed and was straight .............

6/ shocks are fitted .................
7/ and no strenghtening was on TOP.....

8/ and yes no dampener was fitted yet.............................


any way im sure hypo will answer all these in betta detail

[Strange Rover]

These small oscillations (SP) are what a steering dampner is designed to fix. Get yourself a good one with good bushings.

Not sure where you would be best to run it. Could be either between the track rod and diff or the steering link and the chassis. Since you got long shackles and soft leaves Im thinking between the track rod and diff may be the go.

Also try running a bit more toe out. Amazing what this will fix.

Sam

[hypo]

well well well.....

dumbdunce-
castor if fine its been checked, and the \ -- / is looking at it front on. gotta get tyres balanced and try it out as well as change the toe

ruff-
yes drove it home on friday night the same as i drove it yesty the only difference was that on friday night it had no shocks and no spacers, and at one stage had it moving along nicely at 100+ k's and no probs wot so ever. its only since fitting the shocks and spacers..

area54-
37's on yes and no beadlox just ya average 15x8" sunny

Strange rover-
yes shocks r back on and i havent got a steering damper on it yet didnt need one b4 so i havent fittted it but am steering towards it now i think(pun intended)

area54-
i think a damper might help as the wheel goes from left 2 right so dampning the steerin links may reduce this

wendle-
the housing is dead straight apparently the dude that done it has done lots of tailshaft and diff work 4 me and i have never had a problem

bazzle-
something safe ?? WTF ??

v8patrol-
will take it and get the front end all checked out, shocks r fitted and a steering damper is on its way, pix they r in my mebers section go and look there, the additional bracing i done was on top of the diff as there is already bracing on the bottom from the factory,
answers-
1 - yes the hosusing was completly stripped
2 - i rebuilt it and yes everything is tight as per specs
3 - yes it was checked b4 and after the work was done and yes both times i was told it is straight
4 - yes 2" on and 2" off
5 - the welding i did is mainly on top but it has factory welding on the bottom

love_mud -
thanx mate as i have mention above somewhere that i will get the tyres balanced ASAP thanx

A1 -
thanx 4 sticking up 4 me

strange rover -
yes i thinking bout gettin one of the return 2 centre jobs 4 no power steer trucks as the spring is slightly heavier and may help more and i not concerned if the steering is slightly heavier as long as t stops the wobble.


thanx all 4 the comments and suggestions i am considering hydro assist as this will also help my prob i have been told?? but lets not go into a big debate bout hydro as i only thinking bout it at this stage

[beebee]

Hydro is a definate fix for death wobble. Heck - I don't even suffer from death wobble and I'm going hydro!

[thunder]

when i put the internals on ,most of the weights came off and the saturday just gone went down 4 a wheel alignment and balance (160g-190g out)and had the wobbles something fierce after was ok,,,then went to appin on sunday and a few on the drivers side came off(rim stuffed from prev comps) and could not get over 60km even when i tried to change down and floor it....
if it is like mine it gets to the stage where it will shake the whole car..

going to swap the rear to the front and get that balanced...

[Strange Rover]

Hydro is a definate fix for death wobble. Heck - I don't even suffer from death wobble and I'm going hydro!

This stuff is classic - hydro it is

Sam

[Wendle]

These small oscillations (SP) are what a steering dampner is designed to fix. Get yourself a good one with good bushings.

The good bushings bit is important. the whole problem is based around maybe 2-3mm movement at the drag-link. Get a landcruiser style one with press in bushings.

Also try running a bit more toe out. Amazing what this will fix.

That is the first thing all the truck alignment places do to try and iron out problems. Fixes almost everything and comes with free steak knives.

Hypo - 1 degree toe is 16mm between a pair of 37"

[Area54]

I don't think that a steering dampener will be effective enough - I put dual dampeners on my Mav to help reduce the shimmy with my little 34's - no benefit whatsoever. I went down countless directions to fix this problem - still no better, I just learnt to live with it and found ways around streeting the play tyres.

Agressive caster will make it worse - the self centreing will be more pronounced - this will add to the symptom as the wheels correct left, then right, then left and on and on. With the IFS hubs, the wheel spacers and the offset of the rim, you will have a lot of leverage outside of the kingpin pivot point, and the tyre contact patch pivot point is way outside of the projected kingpin pivot point on the ground. With this amount of leverage outside of the kingpin pivot point it doesn't take much of a road bump to start an oscillation effect that is fed by your caster - left then right then left etc. Have you projected the kingpin pivot point on the ground?

You also have a variable that you have no control over - the sidewall of the tyre. The rim won't flex, the tyre will. You can start to see the reason why the steering dampener won't help - there are too many places that can contribute to this problem, two sets of shackle bushes, front spring bushes, the sideways flex of the spring, the sidewall flex of the tyre and the fact that the whole system (front steering assembly) is meant to do one thing - turn the wheels left and right. No sunraysia has ever been made perfectly round and square (in comparison to the accuracy of a well made lathe turned alloy wheel) so here is another influencing factor. The 5mm or so that the steering dampener may firm up is pale in comparison to all the flexible variables mentioned above. Add to this that you are running a tyre with close to an 11 inch sidewall from the rim (that's a lot of rubber that will flex), a luggy tread that will squirm on contact, you will also find that the rim will be moving around slightly when you are driving due to these factors. I agree Hydro will help control the steering gear, but it has no control whatsoever on these above items. With the width you were chasing, did you consider an 80 series housing with less offset on the rims to control the overall width?

[hypo]

yeah im thinking 80 series or gq axles but $$ dont permit ATM thanx i got a few tricks up my sleave will keep u all posted as i find new info

thanx 2 all that gave advice

[Robbo]

I agree with area 54 not a lot can be done with your mods. The shimmy probs in my GU got worse with every inch it was lifted then came a new adjustable panard rod & was nearly undrivable. After more $$ on new wheel brgs cv brgs drag link & heavy steer shock caster plates it just kept getting worse. UNTIL we replaced not so old panard bushes with new (purple coloured) bushes & presto instant transformation. Now running 35 A/T on the street & toyota offset NO PROBS.