TOTM #2: Steering

[Matt S.]

It is that time again. I have put together a basic steering tech page that should help everyone. I will cover D30 options and custom fab stuff. D44 and D60 stuff is already covered so well that I do not feel a need.

First lets start with basic terminology.
Drag link = Steering linkage that connects pitman arm to knuckle
Tie-Rod = Steering linkage that connects knuckle to knuckle (or drag link)
Toe = The symmetric angle that each wheel makes with the longitudinal axis of the vehicle. This can be positive or negative (tires bowed out or tires bowed in)
TRE = (Tie Rod End) Most commonly used steering joint on all vehicles. Strong enough for our applications, not especially keen to high angles of use.
Hiem Joint = (Rod End) Very heavy duty used widely in the racing world.

Aftermarket suppliers for D30 axles.
Phat Jeeps I only am aware of one person using this kit (YellaHeep). Seems to be a good option, but I am unsure of the materials and the geometry changes when using this braket. I have nothing good or bad to say about this kit.
Currie Enterprise sells a great kit that is widely used in the Jeep community. Maintains the OEM steering geometry and uses substantially stronger material and TREs over stock. Good option for most.
TeraFlex High Steer System replaces the passenger side knuckle to get a true cross over steering. Allowing you to raise the drag link substantially over stock. Many modifications may be required to properly use this system. Including sway bar and track bar. Great option for those looking for a better geometry steering system.
Down East Off Road is a completely new steering system that replaces both knuckles and steering linkage. This is a true high steer kit that is by far the best option for the Dana 30 axle.
Rusty's Steering uses oem mounts but connects the drag link to the tie-rod to allow the track bar and drag link to have the same geometry. I personally ran this kit years and years ago and do not recommend it.

There are other variations of these kits, but these show the 5 basic options you have for kits and custom types of steering. The five styles are as follows.

1. OEM style (inverted Y) as shown by Currie
2. Inverted T style shown by Rusty's
3. Over the knuckle steering with separate links shown by Phat Jeep
4. Cross over style shown by TeraFlex
5. High Steer shown by DEOF

Now that we are all clear on the 5 basic types of steering systems, we can discuss building your own. Giving options for material choices, joint choices, and style choices.



Building your own should revolve around one of these styles. Most prefer options 3, 4, and 5. On the Dana 30, doing 4 and 5 can only be done by sourcing your choice of 3 knuckles. DEOF, TeraFlex, or WJ knuckles. Style 3 is most commonly used for the D30 and is more than adequate.

Material choices are key. Using a DOM, Chromoly, or aluminum is important. Thick walled tubing or solid stock. I recommend tubing over solid stock unless you have access to a machine shop.

This should be enough to allow people to chime in with other ideas and options. Please feel free to add to this. I will try to find some threads to add to this later.

Matt

 

[freerider15]

Here's mine using TeraFlex knuckle, ZJ TRE's, 1.5" x .25" DOM, and Go-Fer-It flips. It has since undergone a little change. Now it is OTK, using a TJ pitman arm with go-fer-it flip in it to account for steering radius. I had to put two bends in the tierod to clear the coil mounts though.

http://www.naxja.org/forum/showthread.php?t=57519

This setup has been through hell and back, and hasn't given me many problems at all.

 

[sintax]

1.5" OD .500 wall, Shaffers High Steer arms on 3/4 ton D44 flat top knuckles, FK Hiems (5/8" bore 3/4" shank), Cheap-o single ended ram, Danfoss orbital valve.

 

[Jump This]

Just for info. purposes....

I'm running the Phat Jeeps system also.

Got very tired of replacing tie rods on the trail.
System should be sold with the track bar bracket and track bar.
I'm thinking this system is not breakable. But damn exspensive.
Appears as though adding hydro assist would not be any problem, although
I have not ventured into that realm yet.....
Rick

 

[Kittrell]

Old Sticky

http://www.naxja.org/forum/showthread.php?t=67834

And my own setup

http://www.naxja.org/forum/showthread.php?t=89904

 

[XJ_ranger]

For about 1.5 years ive been running a crossover steering, with 1-3/8" Solid stock with Aurora 7/8" shankx3/4" bore rod ends with normal misalignment spacers.

I ran the tie rod under the knuckle and the drag link over -

Ive beaten the tie rod in and out of straight about 12 times now, and all of my joints have slop in them enough that I get SERIOUS deathwobble... I have decided that if I am going to continue running a heim steering, I will have to carry a complete set of BRAND NEW spare heims everywhere, and plan on replacing them every 9 months on a daily driven rig...

My next setup will be an Invirted T on Dedenbear knuckles, VIA Parts Mike Parts, on top of the hi-steer arm...

This is probably also the thread to mention steering box re-enforcement -

I made a custom front bumper that added 1/4" plate to the outside of my frame, and intend to make an inner plate to get rid of the factory aluminum one and spread load out on the inner part of the frame more, as well as sleve the holes...

Also might want to think about mentioning Ackerman angles and what that does to your steering?

possibly talk about bumpsteer? and how to avoid it when modifying your steering for more clearance... Keeping the trackbar and drag link as close to equal length and parallel as possible...

here is what BrettM wrote for the FAQ -

Short answer:
Bumpsteer is when your wheels turn as a result of suspension compression or extension. This results in poor steering control at speed, and loss of steering angle when articulating the suspension. The way to prevent bumpsteer is to have the trackbar the same length and angle as the draglink (or go to full hydraulic steering). Priority should be given to getting the angles the same, and typically a small difference in length is satisfactory.

Long answer:
With a suspension that travels vertically with compression*, the rigid draglink** wishes to travel in an arc with the pitman arm as the centerpoint. The result is either the draglink turning the knuckles or the pitman arm to allow it to follow its arc, which means either the steering wheel will turn without the tires turning, or the tires will turn without the steering wheel turning, depending on which has lesser resistance (or a combination of both).

The two big negatives of this situation is (1) at higher speeds the bumpsteer causes poor handling and control over the steering and (2) when articulating the suspension at low speeds you will loose some of the range of your steering.

Now in the case of an XJ with a panhard bar (aka tracbar), bumpsteer is less pronounced than an aforementioned suspension which travels vertically because the panhard makes the axle follow an arc through suspension travel. Where problems arise here is when the angle of the draglink is altered through raised steering setups, changing to inverted T, or drop pitman arms. The panhard must then be appropriately adjusted to keep the angles the same and the length as close as possible. I recommend raising the axle end of the panhard because it raises the roll-center of the suspension and makes it more stable.



*like leaf springs or a triangulated link suspensions which doesn't use a panhard

**the link connecting the pitman arm on the steering box to either the knuckle (inverted Y or crossover) or the tie-rod (inverted T).

 

[XJ_ranger]

What spares does everyone carry on the trail?

since building my own steering, ive only carried 1 extra joint, and while I never had a joint fail, i wish id carried at least 2, and want to carry all 4.

I see some guys with spare tie rods, drag lings, sometimes multipul...

how do you decide how much spare steering to carry VS th weight cost of carrying such spares?

 

[IntrepidXJ]

i carry spares of all joints, and a tie rod.....but i'm not concerned with weight

 

[Matt S.]

I carry 2 spare joints. 1 left hand thread and 1 right hand thread. My track bar and steering uses the same joints. I also cary a few extra bolts for the steering... big as bolts come in handy.


I care about weight.

 

[hadfield4wd]

With the d30 and stock steering I carried everything. Drag link, tie rod and all ends. I haven't decided with the new stuff. 1.25 x .25 DOM with Chevy 7/8's TRE's set up for OTK. I'll probably carry complete set to see how it happens the first couple of rides. I am working on a theory of "trail" spares vs "trailer" spares. My Jeep is not light so the weight savings I believe is minimal. I'll figure it out eventually.

 

[jeepnuts311]

what about simple upgrades such as JCR's "1 ton".

i have been running this system for a while and it has been great. my rig is daily driven as well as wheeled. for the bolt-on ability of it, i think it is a great setup. all that needs to be done is three holes need to be reamed.

i am running this system utk as it was designed, but jcr says it can be run otk (you need to specify when ordering) and make a few mods to swaybar links and possibly other things. the tie rod is very beefy tho, i have actually supported the front of the jeep by it on accident before (the jackstand was under there when i lowered the floor jack)

it also keeps the original ackerman angle and on my rig, its parallel to the trackbar, so bumpsteer has not been noticed.

i would love to run something like the $1000. true high steer from down east, but budget is still a factor in my rig.

-tim

 

[IntrepidXJ]

what about simple upgrades such as JCR's "1 ton".

this is the 'advanced' forum

 

[jeepnuts311]

this is the 'advanced' forum

rustys steering is hardly advanced, if it is worth mentioning, then i feel JCRs is worth mentioning.

neither one of these are advanced in the least bit, but i feel that there would be no reason to spend $1000 on histeer for my dana 30.

-tim

 

[cal]

rustys steering is hardly advanced, if it is worth mentioning, then i feel JCRs is worth mentioning.

The JCR and the Rusty's steering are almost exactly the same, except that JCR's is using all off the shelf Chevy ends and some DOM, where Rusty's actually fabricates some parts. Both are inverted T, and covered by style number 2. The post would have been MUCH longer if he listed every varient on each style.

 

[hadfield4wd]

The JCR and the Rusty's steering are almost exactly the same, except that JCR's is using all off the shelf Chevy ends and some DOM, where Rusty's actually fabricates some parts. Both are inverted T, and covered by style number 2. The post would have been MUCH longer if he listed every varient on each style.

Yeah it is all off the shelf chevy stuff put together in one package.

 

[vetteboy]

this is the 'advanced' forum

which is why we've covered bolt-on steering upgrades, and removing carpet and insulating padding.. :roll:

Also might want to think about mentioning Ackerman angles and what that does to your steering?

OK -

The need for Ackerman-based steering arises if you look at the radius that each tire travels when making a turn. In a constant-radius turn, the vehicle is rotating around a central point, and the further away from that point, the less steering correction is needed to execute the turn without scrubbing or binding.

In the above picture, you can see that the inside wheel is turned at a steeper angle than the outside wheel. This is so that each side of the vehicle follows the appropriate arc through the turn. This minimizes scuffing, provides a smooth and predictable turning path, and also helps keep the turning radius to a minimum.

So what does this mean for your steering setup?

The way to implement Ackerman steering on a vehicle involves the relative locations of the tie rod connection, ball joint axis (the line drawn through the upper and lower balljoint), and the rear axle (indirectly, your wheelbase). This diagram shows the necessary relation for all this stuff to work:

Basically, if you draw a line through the tie rod connection on the knuckle and the ball joint axis on each side of the vehicle, you want these lines to intersect right in the middle of the rear axle. This will make the wheels turn in the right amount to properly match the steering arc needed. In the diagram it shows a case where the tie rod is located behind the axle; in most of our cases the tie rod is in front of the axle, which means that the tie rod connection is further outboard than the ball joint axis. This sounds weird at first but if you look at your rig you can sorta see how this is laid out.

The thing to keep in mind here is that it's only the tie rod that matters; the drag link connection doesn't affect the Ackerman characteristics per se, but it WILL affect the steering effort and ratio of steering wheel turns to wheel movement. The tie rod is what couples the two steering tires together to make the Ackerman angle happen.

So when considering things like steering arms and how you want to run your setup, give some consideration to where the tie rod connection will end up when you're finished. Some steering arms let you position the tie rod to accomplish this and some don't. I've driven some trail rigs that have zero or Reverse Ackerman (see diagram above) and the turning radius is miserable. Locking diffs, LSDs, or even 4wd makes things worse as it is but without proper Ackerman it's not a fun time, and you'll be that guy having to make multi-point turns at every twist in the trail.