Bumpsteer???

i am running 33" goodyear mtrs with 4.5" rusty's lift (i am waiting on my spacers and shackles). the highways around me are under construction so the roads are a mess. when i drive on them my jeep pulls left and right. and also when i change lanes it pulls the way that i am turning. what is this? and how is it fixed? right now the sway bar is disconnected, it did not come with one, so i bought one and am working on the disconnects. will that fix it? if not what will?

After you installed you lift, did you get an alignment? Sounds like a toe-in issue.

Yeah, if you haven't adjusted your alignment, chances are that's part of the problem. Check your toe and adjust it, or have it adjusted accordingly.

jeeperzevanxj said:

i am running 33" goodyear mtrs with 4.5" rusty's lift (i am waiting on my spacers and shackles). the highways around me are under construction so the roads are a mess. when i drive on them my jeep pulls left and right. and also when i change lanes it pulls the way that i am turning. what is this? and how is it fixed? right now the sway bar is disconnected, it did not come with one, so i bought one and am working on the disconnects. will that fix it? if not what will?

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Running without the sway bar is allowing an excess amount of body roll. With the increased angle of your control arms, this is causing roll steer. When the Jeep body rolls to the right (turning left), the control arms on the right side are compressed and the left arms droop. This pushes the axle forward on the right and rearward on the left which causes a steering motion to the left. Just the opposite happens when turning right. In each case, the roll steer adds to the steering imput to increase the overall turning effect (oversteer). Assuming you have the stock steering setup, it is also contributing a minor amount of roll steer due to the slight difference in length and angle of the track bar vs drag link.

Something else to consider is your wheel backspacing. With the 33" tires you probably went to a wider wheel. What is the backspacing? If it's in the 3 1/2" to 4" range, that can cause the Jeep to pull to the side when one wheel hits a bump and the other doesn't. To further complicate matters, if you haven't corrected your castor after installing the lift, you Jeep will tend to wander and lack an "on center" feel to the steering.

To add the 11% you didn't get from the guy who claims he's 10% younger than I, what you are experiencing isn't bump steer.

Bump steer is what you get when steering components aren't properly aligned, and compressing the suspension (both wheels, like hitting a dip in the pavement) causes the vehicle to steer to one side with no steering wheel input, and extending the suspension (both wheels, like topping a rise) causes it to go the opposite way ... again w/o steering wheel input.

The behavior you describe can be a function of roll steer, as MaX pointed out, but it can also be a function of wide tires with good tread and loose steering components such as tie rod ends.