I recently got my front end aligned. It seems like ever since I installed the UMI K-member, the steering hasn't been quite right. When I'm driving in a straight line, the car wants to "jerk" to the left and right. It's pretty subtle but it seems like a caster problem to me. Here are the specs:

Left
Caster Initial: 5.1 New: 4.9
Camber Initial: -0.4 New: -0.3
Toe Initial: 0.12 New: 0.03

Right
Caster Initial: 5.6 New 5.5
Camber Initial: -0.6 New: -0.5
Toe Initial: -0.09 New: -0.12

Thanks in advance!

 

Hey, good morning.

Does it jerk during normal smooth road straight line driving? Those specs are pretty much in range.

With the toe settings is your steering wheel centered (just curious)?

How about your tire and shock condition?

ramey

 

Left
Caster Initial: 5.1 New: 4.9
Camber Initial: -0.4 New: -0.3
Toe Initial: 0.12 New: 0.03

Right
Caster Initial: 5.6 New 5.5
Camber Initial: -0.6 New: -0.5
Toe Initial: -0.09 New: -0.12

ALL the "old " were "better" ( if you want to split hairs) than the new settings.you had more caster and more toe in . With the new settings you have a very little bit of toe out which could cause a little bit of road wander, but should not cause any jerking, your new setting are fairly good but I would like to see a little toe in. I suggest you check all tie rod ends for slack also as suggested check your tires and shocks
Johnny

 

I would also double check that the steering rack bolts didnt loosen up. It can cause the symptoms you're experiencing.

 

You're left and right toe should be more closely matched. It looks like one is out and the other is in right now. They should both be in.

Also, check the ball joints. You might have a worn one (probably an upper).