Loose steering / bump steer?

[Mickerification]

Hi guys so this is my first time here and I figure this is the best chance I have to get down to the issue.

So I recently bought a 97 wrangler.
Its lifted and has bigger tires. Anyways when I'm driving it it seems to dance all over the road.

The alignment is proper. Ball joints all fine. Everything seems to be solid whilst it's in the air.

So I'm not sure where my issue is coming from.


If anyone has any advice or maybe a question (I'm sure I'm being to vague in this description) that would be so helpful.

 

[Jerry Bransford]

Take several good sharp close well-lit (use a flash) photos of your steering system and post them here. By seeing how it's configured there's a good chance the problem can be determined.

In particular ensure you post photos of the Pitman arm from the side and of the track bar mount from the driver's side. The whole steering system from the front too.

 

[Mickerification]

Take several good sharp close well-lit (use a flash) photos of your steering system and post them here. By seeing how it's configured there's a good chance the problem can be determined.

In particular ensure you post photos of the Pitman arm from the side and of the track bar mount from the driver's side. The whole steering system from the front too.

 

[Jerry Bransford]

Ok on all that and your geometry looks fine. I'd next look at the toe-in and caster angles to see where they are. Either can cause steering instability. Also make sure your tires are not overinflated. Exactly what size tires are they and exactly what air pressure is in them?

 

[Mickerification]

Hmmm I don't know how to adjust caster on these things this is my first jeep.

The tires are 33x 12.5
And they're 28 to 30 psi all around. So not over inflated. As far as I'm aware.
first time for me with these kinda tires.

 

[Jerry Bransford]

26-28 is a better pressure for that size tire when under a Wrangler TJ. 26 psi when the Jeep is lightly loaded, 28 psi when it's fully loaded with people and/or gear.

 

[Mickerification]

Ok I'll drop it down a little. But still I mean im like all all over the road. Maybe I should check the alignment again and shake things down again something must be loose cause I just have no clue why I'm all over the road. I know it'll never be the same as stock cause it's lifted and stuff but I'm crazy all over the road.

 

[Jerry Bransford]

Just because your Jeep is lifted doesn't mean it can't ride, handle, and steer just fine. My TJ is on 35s with a 4" suspension lift plus a 1" body lift and it does all of those things very well.

A rough ride, bad handling, or unstable steering is abnormal and just points to it having been built/modified by someone who didn't know what they were doing.

 

[tworley]

Never fall for the "its a jeep" line. When everything is correct and in good condition there is no reason you cant run 70 mph with one hand on the wheel.

Do you have adjustable control arms?

 

[Mickerification]

Never fall for the "its a jeep" line. When everything is correct and in good condition there is no reason you cant run 70 mph with one hand on the wheel.

Do you have adjustable control arms?

View attachment 65248

I'm not entirely sure I'll look tomorrow. What should I do if they're not adjustable. Or even if they are adjustable.

 

[ac_]

if they are adjustable, you can adjust your camber, of which I seem to have a lot of camber issues myself after my lift. I am still trying to find the sweet spot, but I can drive 70 with one hand on the wheel, but it gets kind of squirrely after that.

My TJ is a 98 with 33's and 4 inch lift

 

[Mickerification]

if they are adjustable, you can adjust your camber, of which I seem to have a lot of camber issues myself after my lift. I am still trying to find the sweet spot, but I can drive 70 with one hand on the wheel, but it gets kind of squirrely after that.

My TJ is a 98 with 33's and 4 inch lift

I gotcha so basically you guys are saying that the dancing all over the road is more or less an alignment issue.
Toe, camber or caster( still not sure what caster does) but it's probably something in that category. Or like steering box or Pitman arm.

It's not anything with the fact it's lifted and on big tires?

 

[ac_]

caster is the angle of the front axle forward to backwards. It definitely has something to do with how our Jeep steers.

Axles out of alignment in relation to the frame can too.
If your axles are off that can make a difference too. What I do to check is measure from the front of your axle tube to the middle of your crossmember bolt hole in the rear and the opposite in the front. That will give you an idea if your axles are straight. An angle gauge is what you need to check camber, but if you don't have adjustable control arms neither of those matter, because there is nothing you can do about it if it is stock, but if it is way off you man need to purchase adjustable control arms to compensate.

And finally toe as you mentioned which is adjustable.

 

[Akitadog]

Caster is the tilt of the pivot points front to back.
Caster is what makes your wheels return to straight when you let go of the wheel in a turn. Also makes the vehicle more stable at speed.

 

[Mickerification]

Caster is the tilt of the pivot points front to back.
Caster is what makes your wheels return to straight when you let go of the wheel in a turn. Also makes the vehicle more stable at speed.
View attachment 65613

Ok so in order to adjust caster what would I need to replace.
The only thing that's able to be adjusted anymore is the toe in and out, the tirod if that's what it's called in the jeep world.

Ok so let me kinda elaborate on the situation. I really was trying to figure it out today.

Anyways you know how like on the highway the road slopes to the right on the slow lane and then the next lane to the left (or however many lanes) slopes to the left for rain to run off easier.
Well when I transition from a right slope to the left slope (switch lanes) I feel the entire jeep like really wanna pull me that direction like alot.

That's really the root of the evil I have with this thing.

 

[ac_]

Ok so in order to adjust caster what would I need to replace.
The only thing that's able to be adjusted anymore is the toe in and out, the tirod if that's what it's called in the jeep world.

Ok so let me kinda elaborate on the situation. I really was trying to figure it out today.

Anyways you know how like on the highway the road slopes to the right on the slow lane and then the next lane to the left (or however many lanes) slopes to the left for rain to run off easier.
Well when I transition from a right slope to the left slope (switch lanes) I feel the entire jeep like really wanna pull me that direction like alot.

That's really the root of the evil I have with this thing.

the word you are looking for is crown, and I know exactly what you are saying. it could be a number of things, but caster can be one of them. To fix it is probably your most expensive option so you want to know for sure that is an issue

You need to get an angle gauge and find out what your pinion angle is. I kind of have the same exact issue that you are talking about myself. I have adjustable control arms and when I had a two inch lift I had it steering perfect at about 7 degrees, but since I added the lift to 4 inches, I have lowered again to keep it around 7 and it still does exactly what yours is doing, but only at high speeds. I am trying to dial it in, but not really sure where to go myself other than to take a whole day out and play with it some more.

right now with my caster at 7 my driveshaft angle is completely off. So I am thinking about starting over.

If I were you I would buy an angle gauge and see where you are. I was perfect with a 2" lift and 7 degrees, but not so much at 4" and 7 degrees. I was going to start a thread to see what others had with a 4" lift.

But for you a cheaper option to start with might be to check your tow and make sure it is really close and see if that helps. buy and angle gauge and see how far your pinion angle is off.

I hope people with more front end 4 link suspension will jump in, because your explanation I feel was articulated very well and makes sense. And since I am not 4 link front end suspension expert yet I don't feel I should probably be advising you with this. I just wanted to give you the cheapest place to start looking. I am hoping to get schooled on this myself in the end.

 

[Richard Brust]

It's not anything with the fact it's lifted and on big tires?

I have a 98 TJ that I just put the OME kit on - supposed to be a 2" lift but I think my shocks/springs were so worn that the end result was 3". I still have the stock tires on, have not replaced with larger tires - and I have the exact same issues as you do. Any bump or even dip/rise in the road seems to cause it to just feel like I'm on ice. ( this kit also came with the steering stabilizer )

As Jerry mentioned above, this clearly could be b/c of being " built/modified by someone who didn't know what they were doing " - but I did take my time and double/triple check everything I changed.

i was actually thinking of alignment, but when I let go of the steering wheel (as long as I don't go over anything) it _does_ stay straight, but that's probably not an accurate test.

p.s. I also added a .75 coil spacer to just the front

 

[dimension12]

When you install a lift the toe in will increase I believe. There is a sticky thread here that will walk you through setting the toe.

 

[Jerry Bransford]

When you install a lift the toe in will increase I believe.

You are exactly right. Lifting the frame raises the steering box which pulls on the drag link/inverted-Y steering system which pulls the knuckles together which pulls the fronts of the tires closer together.

 

[dimension12]

You are exactly right. Lifting the frame raises the steering box which pulls on the drag link/inverted-Y steering system which pulls the knuckles together which pulls the fronts of the tires closer together.

They have toe in causing the squirmy steering.