crossover and bump steer

[boz42]

The length of the draglink is what improves bump steer not the angle or bend. The only time I know the angle matters is when you have a panhard bar on the front axle like a 73-79 ford coil spring radius arm set-up. In that style application the draglink must be parralel w/ the panhard bar.

 

[miniwally]

I think i see the light.
This "steering feedback" was non existant before the crossover. BUT i do have a new stabilizer....

As far as the drag link thing...
I think im going to stay confused. Im not comprehending how the bend in the drag link doesnt reduce bump steer, but helps geometry. Im guessing because the height difference between the steering arm and the pitman arm is causing triangulation so as the axle goes up the drag links triangle flattens which causes the feedback... Which would be why a bent link doesnt help...

Am i thinking right? Should i think about another stabilizer? It seems to drive straight... as long as the bumps arent too big...

Take a piece of paper:

On the lower left side put a dot. This is the axle knuckle
On the upper right side put another dot. This is the pitman arm.
This is how the truck looks if you set on the ground infront if it.

Now measure the distance on the paper between these two points.
After that draw a line that approximates the bent drag link you have.
Then draw another line and make it have two 90 degree offsets to achieve the same vertical drop.

Did the two dots on the paper ever move, change distance or otherwise relocate themselves?





NO.

It doesn't matter how you connect the dots and what the shape of the drag link is as long as those two dots are connected together.

Now if your drag link is too short or long you are going to get different turning radiuses left and right.

Following so far??

 

[Shawns84]

Yup... Sort of. Kinda lost me with the dots thing. But kinda see what you mean. Drag link connects the two, dont matter what shape it is...

That said, moving the dots more level with each other will lessen steering feedback?

 

[YZEATER]

your driving a lifted truck with modified suspension. it's not gonna drive like a sports car. if you have really soft soft springs your axle is going to move up more, therefore shortening/pushing the draglink, and turning the wheel.

 

[miniwally]

Drag link connects the two, dont matter what shape it is...

That said, moving the dots more level with each other will lessen steering feedback?

Ok your starting to see the light.

Now as you sit there and look at the front of the truck or dots on the paper. Imagine a side force pusing the axle to the side. The leaf spring bushings have some give to them so lets say that the axle moves 1" to the side.

All of the sudden the Draglink just had to get 1 inch shorter or longer depending on the direction of axle movement. It can't change length so something else has to take up the length change.

In your case the steering wheel is moving. Steering feedback
If you go over the same bump and hold on to the steering wheel as tight as possible and don't let it move then the tires will have to steer one way or the other. Then the vehicle will dart one way or the other. Bumpsteer


Kinda the same but not really.

BTW the same thing happens as the axle moves up and down as the suspension travels.

 

[smalltruckbigcid]

The backlash may be a bit loose, but not way out of the norm.
By bump steer i mean when i hit a roller or something, anything that makes the suspension move, the wheel jerks in my hand. My turning radius is not quite right yet cause the drag link i have is a couple inches too short and i wanted to drive it to see how it acted. (the wheel is slightly cocked) But it is definately better than before. I can almost turn it around on a narrow two lane road now.
My bump steer issue is the one bothering me.

How far are your drag link ends threaded into your drag link? If yours are turned in all the to the end then they are screwed in to far. I did crossover for a friend on a 6 inch lift of unknown brand and we got the turning radius perfect side to side. We got the box centered with the draglink and then using the Jeep XJ shaft swap got the steering wheel re-centered so it looks and works like stock.

You may have the right length drag link but its not adjusted right yet. Flexy long travel suspensions usually have more steer than the stock stuff and soft springs compound this problem. Hope you see the reason I asked what you were calling bumpsteer, it got everybody on the same page
George

 

[abig85]

yeah i kinda figured the 1/2 and 1 ton were the same. they looked the same... but that was the only thing i messed with and it helped. im sure messing with that adjusting screw had something to do with it.