LN106 hilux steering issue

[yourlocalheadhunter]

So after moving my front diff forward i have since encountered a bad steering issue, I redrilled the spring perch on 1 side and move the diff forward i think its 35mm as alot people do to clear big tyres.

I already had an adjustable drag link and have shorten that right up to suit. But my issue now is this thing is dangerous to drive on road.

When turning a corner even slightly the ute tries to carry on turning as the steering refuses to return to center after turning like it should. The steering feels heavy suddenly but im unsure what it is?

Wheel alignment today shows that is fine, so some where i have a issue an im unsure what?

cheers Guys

[Smurf]

I'd guess your castor angle is out, as your diff moves forward along the spring the diff rolls slightly changing the castor angle, not much but perhaps enough to affect the self centreing

[yourlocalheadhunter]

I'd guess your castor angle is out, as your diff moves forward along the spring the diff rolls slightly changing the castor angle, not much but perhaps enough to affect the self centreing

I also have been thinking this, the guys at the wheel alignment shop put it up and said its all bang on, but im guessing they are looking at factory specs. should my castor be out the factory spec since its lifted with diff forward?

cheers

[mudlva]

So after moving my front diff forward i have since encountered a bad steering issue, I redrilled the spring perch on 1 side and move the diff forward i think its 35mm as alot people do to clear big tyres.

not wanting to be a smart bum here but shouldnt that be drilled on both sides??
otherwise you will be turning a continous turn when steering straight

I already had an adjustable drag link and have shorten that right up to suit. But my issue now is this thing is dangerous to drive on road.

wee whiles back you were talking of fitting longer shackle arms, did you do this?
extended arms plus moving diff will affect the caster quite dramatically

When turning a corner even slightly the ute tries to carry on turning as the steering refuses to return to center after turning like it should. The steering feels heavy suddenly but im unsure what it is?

thinking out side the square on this do a basic set up test.
disconnect drag arm
turn steering wheel fully to the left, mark tdc on wheel with a bit of tape
turn wheel fully to the right counting total turns plus balance of turn, use a little peice of tape to mark this tdc spot
turn wheel back to the left in exactly half the distance traveled, this is steering box center point, mark this again and dont allow the wheel to move.
to center road wheels
ran a string from rear wheel up to and past front wheel on rhs. move wheel to align with string
do the same with the lhs
move the wheels into the middle area between the two lines, this will be accurate enough.
what is the length like on the drag link?
adjust to suit if its out
i suspect it will be.


Wheel alignment today shows that is fine, so some where i have a issue an im unsure what?

cheers Guys

wheel alignments dont do much on beam axles that have been modified and will not show steering box or steering link alignment

im assuming that the tie-rod and toe is set correctly??

[yourlocalheadhunter]

Sorry i didnt give the details overally correct,

1 perch already has the hole factory to move diff forward its just a case of drilling the opposite perch to match which was done so both sides were moved forward 35mm.

Yes extended shackles were fitted they measure 6.5 inches long, also while i was doing that i found the front leaf hangers to be cracked badly so those were removed and a piece of 50mm box was added then new hangers mounted to that so they sit 50mm lower then factory ( we thought this would help the pinion angle slightly ).

thanks heaps for the input ill try get it in to the shed tomorrow and do as u say and see what i come out with,

The wheel alignment tech says its all ok but hes meaning in factory specs im guessing, this thing has around 4 inches of suspension lift as well as the diff forward so i find it hard to use his words as a direction to be looking. but he said toe etc is fine and castor was around 5 degrees if i remember righty

cheers

[mudlva]

you can get caster correction wedges that fit in between the leaves and the axle to help roll the diff to get better caster.

skid on here would be better to chime in if 5d is acceptable or not.

check every thing else first and if the steering is still crap then the wedges will be the next step.

dropping the rear spring purchase is definitely in your favour.

on a side note, have you braced the extended shackles?

have you fitted anti inversion stops?

[Smurf]

When you shortened up your drag link did you ensure your steering box was centred? Also with the lift you have are the ball joints on the ends of the draglink binding at all, they could be catching and preventing the steering returning, highly unlikely though.

[yourlocalheadhunter]

you can get caster correction wedges that fit in between the leaves and the axle to help roll the diff to get better caster.

skid on here would be better to chime in if 5d is acceptable or not.

check every thing else first and if the steering is still crap then the wedges will be the next step.

dropping the rear spring purchase is definitely in your favour.

yeah we try sort work it out so everything was the same before but 50mm lower roughly

on a side note, have you braced the extended shackles?

No they are not as i didnt think they were long enough to need to be also they are made out of 40x10 flat so almost double the thickness

have you fitted anti inversion stops?

extended bump stops? if so yes i have though i found out today my leaves still reverse slightly when full cross axles

[yourlocalheadhunter]

When you shortened up your drag link did you ensure your steering box was centred? Also with the lift you have are the ball joints on the ends of the draglink binding at all, they could be catching and preventing the steering returning, highly unlikely though.

i centered best i could by measuring but tomorrow ill try the method as above and see if its out, i like to think we got it near bang on but tomorrow shall tell. i beleive they are not but ill triple check tomorrow,

cheers for all the suggestions guys makes finding this issue alot easier thats for sure

[mudlva]

humm could be on to something here now

with the moved diff adding more weight onto extended arms im thinking that the arms are folding over as you turn.

i would suggest adding a box section center of the arms to hold them perfectly square and straight.

anti inversion bar is a piece of say 40x40x6 angle welded onto the shackle to stop it from folding over and rearwards.

this happens when you hang a wheel and at the same time move forward. the springs compresses and allows the shackle to roll over back onto the under side of the chassis and becomes bound up in that position, it will end up snapping the main spring with the bush eye in it.

quick reversion; check the steering box center in relation to the wheels and box your shackles then take for a test drive ad report back

[Smurf]

I would be bracing your shackles at that length too, either weld in some steel or drill them and run a bolt through a crush tube, this will remove any lateral/sideways movement in the shackle that could let your diff move out of square which could also have an impact on your steering

[Petemcc]

The last one we did drove the same without caster wedges. Put them in and it was good as gold

[mudlva]

here ya go

http://www.lowrangeoffroad.com/pinion-castor-shims.html

[mudlva]

did ya sort the bump steering issue out?

what was the steering box to wheel travel alignment like?

did you look into those wedges???

so many questions ...so little time...

[yourlocalheadhunter]

did ya sort the bump steering issue out?

what was the steering box to wheel travel alignment like?

did you look into those wedges???

so many questions ...so little time...

sorry ive been away with work doing 12hr days today maybe the day to try many of these suggestions, i will defiantly be back with answers

[yourlocalheadhunter]

The last one we did drove the same without caster wedges. Put them in and it was good as gold

Might sound like a dumb question, But what way round did you put in the wedges to cure your issue?

cheers

[ChurchurDan]

If you want to increase positive castor( this is needed for the steering to self center and go in a straight line) you want to roll the diff rearward so the wedges will have the thick end to the front.

[Checkerhead]

with the moved diff adding more weight onto extended arms im thinking that the arms are folding over as you turn.

Mudlva, between the above comment and you saying something about him having lowered the rear spring perch, I think you are forgetting that Hiluxes run the shackles at the rear of the leaf. Unlike cruiser which have them at the front. As such, moving the diff forward would actually take weight off the extended arms, thus reducing there tendency to fold over. Of course we might be talking at cross purposes.

What size tyres are you running Headhunter? (sorry your full name is way to long to type). Generally bigger tyres means more caster. For example look at Skidmarks "first surf build". Cert guy said factory spec caster was the min that he would accept, but not worried if he had more caster than factory spec. 5 degrees on 35" tyres should be zero problem. Also, I think it wouldn't give the "really heavy steering all of a sudden" that Headhunter mentioned.
Any way more caster means more "self centering", so "too much" caster (ie 5 degrees in this case) wont be the problem.

I have no idea what the problem/answer is. It sounds more like a "catching" or "linkage rolling over" type thing rather than just a caster or toe type thing.

I assume you suitable adjusted the length of the control arm that goes to the top of the diff (now that you have moved the axle lower and forward)?

One potential solution is to go cross over steer. The J arm set up is (apparently) notoriously bad once you get longer travel. Also (apparently) this makes them steer "better than factory" in off road type situations.

Can you replicate this problem just sitting in your driveway? Can you get someone to do it (steer) while you watch all the linkages to see what is going on? (Sorry if that is the first thing you tried).

[mudlva]

Point taken was thinking of cruiser set ups

My bad.

Back to the shed for me....

[yourlocalheadhunter]

Ok so a bit of a update, taken alot longer then i thought to find time to get on to this issue.

I have fitted castor wedges to the front and its made a huge difference, not perfect but defeintly better. im going to go slightly bigger in the wedge and see if i can get it where i want it.

also bracing the shackles to be safe. fitted new 35s also.

[tomsoffroad]

Is the drag link catching on the u bolts?

[yourlocalheadhunter]

Is the drag link catching on the u bolts?

Hey mate, doesn't appear to be. I notice a bit of rubbing on the rubber bump stop as ive relocated that foward with the diff but it has rubbed through so i believe it no longer does.. it was quite a deal setting the drag link on the right angle with bolts facing correct way to miss everything!

From some one who builds these things daily have you have or seen this sort issue before ya self?

cheers

[tomsoffroad]

I've seen u bolts catch. The best fix is hi-steer tbh. Do that and you'll never go back.

[tomsoffroad]

Another idea.... haven't got a bent or dented steering dampener?

[Checkerhead]

Another idea.... haven't got a bent or dented steering dampener?

Good "out of the box" thinking there Tom. Just doesn't sound like a caster type problem.

[tomsoffroad]

Another idea.... haven't got a bent or dented steering dampener?

Good "out of the box" thinking there Tom. Just doesn't sound like a caster type problem.

I agree. I am for +6° castor . Factory is +3.5° .. or some thing close to that