stonecrusher steering= bad bumpsteer??

[el burro]

So what do u guys think? Im I asking to much of the steering setup and is their always going to be a little bump steer or do I need to make it flatter or just set the linkage up differently? And how r those airbags? I wouldn't mind getting rid of my sway bars for those. Would u recommend airbags? Have u had one get punctured?

 

[Hagan]

Can the upper link be fabbed into the shape of an S. So its level to the pitman arm but curves down and is level with the passenger tie rod. Then the steering arm attaches to the that and goes to the drivers side tie rod. If that makes any sense? Basically instead of using a HUGE drop pitman arm, make an arm (strong obviously) in a shape to make up for the lift? Or is that dangerous?

 

[el burro]

that would be a good idea. I think if where to do that I would have some weld shop make me a new passenger to pitman link that uses ur standard tie rod ends so I wouldn't have to drill out my extreme drop pitman arm then make the drivers side linkage attach to the passenger to pitman linkage in the back like a stock one would do and I would incorporate that bend like u where saying so it would give the linkage room so it won't hit my I beam drop brackets when it is turning or flexing, yet still be out of the way of the passenger and driver side linkage from hitting eachother.. That's basically is my problem now. I have bumpsteer, I cant lower my pitman arm with out cramming each side of the linkage into eachother. Does any one else have this problem?

 

[Hagan]

Yeah the only problem I see is if the s bend isn't strong and you hit a hard bump and it bends it. I'm assuming thats why all steering setups i've seen are all straight. I've been researching a lot of setups and what I am going to do when I lift mine and I'm not sure. I'm not looking forward to spending $500 on a superrunner kit.

 

[el burro]

Yeah the superrunner kit looks good. Honestly I really want to try that setup. But unfortunately I drilled out my knucks for this stonecrusher setup. Does any one no if there are any tapered sleeves to except the stock tie rods? Or does anyone know if the superrunner kit can easily be fabed up to use rod ends on the knuckles instead of the tie rods?

 

[legoms013]

Can the upper link be fabbed into the shape of an S. So its level to the pitman arm but curves down and is level with the passenger tie rod. Then the steering arm attaches to the that and goes to the drivers side tie rod. If that makes any sense? Basically instead of using a HUGE drop pitman arm, make an arm (strong obviously) in a shape to make up for the lift? Or is that dangerous?

Bending a rod into a shape, still does not account for the difference in heights. There is still a discrepancy that has to be dealt with, simply bending something thinking it will fix it will not, this does not change the fact that there is a difference between the pitman arm pivot point height and the axle beam pivot point height. Shortest distance between two points is a straight line, but even a curved and shaped one still only acts like a straight rod...

 

[Hagan]

Bending a rod into a shape, still does not account for the difference in heights. There is still a discrepancy that has to be dealt with, simply bending something thinking it will fix it will not, this does not change the fact that there is a difference between the pitman arm pivot point height and the axle beam pivot point height. Shortest distance between two points is a straight line, but even a curved and shaped one still only acts like a straight rod...

Then how are we going to help him fix his bump steer?

 

[legoms013]

Not by your suggestion, b/c the tie rods are already flat.

He is noticing the bumpsteer because it is characteristic of the StoneCrusher style steering to do what he has described. Really friggan soft coils don't help the situation either.

 

[el burro]

Well it sounds like im just gonna have to get use to the bump steer. Thanks for all the info. Just out of curiosity, how is the the superrunner kit with bumpsteer?

 

[4x4junkie]

The truck has 4 maybe 5 inches of lift. And im using a typical 2 inch drop pitman arm..

^^
That's the problem right there, no ifs, ands or buts. You need another two inches drop at your pitman arm.

Like said, S-bends cannot fix a geometry issue, however they can help with clearance issues. A small bit of bend in a solid rod steering link shouldn't be an issue (provided it's thick enough) if you need it to clear your d-side tierod, however I wouldn't go too crazy with it (such as in the pic I used in that steering article depicting the crossover setup).

As for the Superlift (K-link) kit, I don't seem to notice anything in the way of bumpsteer since having properly aligned the centerlink with that of the axle pivots on mine (at least not under any normal circumstances). I haven't yet experimented with a Stonecrusher style linkage though so I can't really offer you a good comparison on it. However it does seem to me it shouldn't have an objectionable amount of bumpsteer if everything is on the proper plane it should be on (pitman arm = axle pivots).

I assume you've already tried the SJ FA600 arm with the stock (OE) linkage?

 

[legoms013]

Well it sounds like im just gonna have to get use to the bump steer. Thanks for all the info. Just out of curiosity, how is the the superrunner kit with bumpsteer?

It is still there, but it is drastically less (now that the pivots are where they should be since I modified it)...I really only notice it b/c of the amount of travel I have compared to stock that gets used when driving. About 4" of travel gets used in normal highway driving, so bump-steer is almost non existent then, very much like stock so to speak. Offroad, when going fast, or coming of a ledge and utilizing more like 5"-11" of travel, yes, the bumpsteer is still there obviously since at the extremes the tie-rods don't exactly follow the same arc as the beams, but it is very minimal.

However, the bump-steer is way less than what it was. It used to be so bad that I would eat through draglinks about every 20k miles, since the TRE at the pitman arm was operating at a extreme angle, and getting huge axial forces constantly. From an engineering standpoint, flat tie rods mean that the forces are less since the bumpsteer doesn't exist, and aren't pushing/pulling on that joint with that large magnitude of forces anymore.

I've run stock, with a 2" drop arm, which was horrible @ 3.5, 4, & 5.5" of lift.

I've run stock, with a 4" drop arm, which was better, up to 5" of lift.

I've run a 1-ton chevy TRE version of the StoneCrusher setup, which still had unacceptable amounts of bumpsteer, with a 4" drop arm @ 6.5" of lift.

I've ran a stock style setup, using 1-ton chevy TRE's which wasn't too bad, but still sucked in general, and left more to be desired, on a 4" drop arm @ 6.5" of lift.

I've run a SuperRunner kit, with an UN-MODDED centerlink, and 1-ton TRE's and a 2" drop arm, and that sucked, though I will say that less bumpsteer was perceived since the tie-rods are nearly equal length and the forces almost balance each other out if they occur at the same time. Still not good though. This was @ 6.5" of lift.

NOW I am running a SuperRunner kit, with the centerlink pivots dropped 2.5", to match my lift bracket pivot points, 1-ton TRE's, and custom idler arm, which makes the tie-rods FLAT. THIS is by far the best system to date. Drives like stock on the highway, with minimal bumpsteer offroad. And it has this little added side benefit of being beefy, durable, and simple to work on or replace individual components. I can get pics if you want...or if you do a search they are floating around on a few threads. Still @ 6.5" of lift.

I have run 4 different systems, and I will say that the modded SuperRunner gave the best results. For me the StoneCrusher didn't work b/c of my lift height, but it should work no problem for the 2-4" lift range. It may sound like I am biased towards the SuperRunner thing, which I am, but this is only b/c of the amount of lift I wanted to run, for shorter lifts, other styles can work just as well.

Just remember, the pivot(s) for your tierods, must be no more than about 1" in vertical distance from your drop bracket pivot points.

See the very last picture @ the bottom of the page here:

http://www.therangerstation.com/Magazine/winter2008/steering_tech.htm

IMHO, single best article here on TRS ^

 

[Hagan]

Thanks for the help guys! I honestly have read hours of info in the tech section and must of missed that!

I really want to see some pics of your setup. I read a thread where you posted pics of your setups but didn't fully understand how your setup works. And one of your pics was dark and I could not see.

I'm also interested in how the swingset style steering works?

 

[legoms013]

Here are some pics of a great Swingset style steering system. Basically puts where the tie rods pivot in a direct line with the axle pivots and the radius arm pivots....the perfect location. I would presume this person has little to no bumpsteer.

Link: http://www.explorerforum.com/tds_02/7.html

Note its complexity though, and the low hanging tierods. Not a huge deal, but they are the trade offs for no bumpsteer. On mine I chose stronger straight tie-rods that are up a little higher, but as a result I still have some bumpsteer (not much though )

Here is mine:

 

[el burro]

So I think im either gonna get a swing set style steering set up or maybe see if a shop can build me a superruner style set up. I give up on trying to correct this bump steer. I think the coils are just to soft for the stonecrusher set up. I want to have as perfect handling as I possibly can! Does any one know of any good 4x4 shops that knows ttb steering really well in Oregon or southern washington? Maybe a prerunner shop or something?

 

[AaronC]

So I think im either gonna get a swing set style steering set up or maybe see if a shop can build me a superruner style set up. I give up on trying to correct this bump steer. I think the coils are just to soft for the stonecrusher set up. I want to have as perfect handling as I possibly can! Does any one know of any good 4x4 shops that knows ttb steering really well in Oregon or southern washington? Maybe a prerunner shop or something?

Your just too far north.. Head down into CA and there is a lot of guys who can handle the task.. Problem is... Be prepared to fork out $2k.. A true dual swing setup will eliminate bump steer all together will run you more..


I built my own.. Cost me around $550.00

*NOTE* the steering box is not in the truck on the 2nd picture down..