Steering wheel wobble when braking at higher speeds..

[geoprz]

I’ve been having steering wheel wobble when being a little hard on the brakes at higher speeds for a while now and some pulling to the right and left. It’s not necessarily a perfect straight line feel when going hard on the brakes. Changed the pads and rotors two summers ago. Wheels are balanced. Front tires are like new still. There is slight play in the front control arms I am told by an indy and the dealer. My question is can the control arms be that much of a problem? Or something else?

Brought it to a performance shop for other work today (stainless steel stop tech front brake lines and bronze bushing guides) It’s unrelated to the issue since it’s been on going beforehand. Just thought i’d throw that out there. Barely noticed a difference in the brake pedal firmness. I was hoping for a noticeable difference in the pedal feel. Maybe it’s masked from the steering wobble.

[strad]

Your issue can be caused by bad bushings in the front suspension. But also by rotor issues. You need to determine which of those is more likely. Being only under braking, more likely the rotors. You need something to check runout (I think that is the term) basically checking that the rotor is straight all the way around and the dial indicator doesn't change values as the rotor is turned.

[geoprz]

If the rotors check out that they are okay what would be the problem then? I have brand new coil overs installed two summers ago so i don’t think it would be suspension related.

[Timm]

All explained here:

https://www.meeknet.co.uk/E38/E38_Shimmy.htm

[kouks]

Did not read Timm's piece, but had this on three different vehicles, including a Suburban, each time it was the brake rotors.