Heeeeeeeeelp.

In the last 6 months my 2004 MCS (70K miles) has picked up a wheel wobble when I brake at any speed above 30 MPH. This manifests itself in a shaking steering wheel. I have replaced a LOT of front end stuff but nothing has fixed it (see list below) I think it could be the inner ball joints or the hubs but I'm looking for suggestions and help. I autocross the car and take it to the track occasionally.

Brake pads (3 times EBC)
Brake rotors (2 times EBC slotted and drilled)
both struts (OEM to H&R coil over)
stut top mounts (OEM to adjustable)
Outer ball joints
driver side track rod end
brake fluid (to ATE blue)
wheels (16" racing set does the same thing)

A few observations; under light or heavy braking the car does not pull to the left or right stays straight. As it does not do it if i just use the hand brake i strongly suspect the problem is in the front end. Does it with DSC on or off.

any ideas????????

 

First thing I would check is front brake rotors that are warped or have thick and thin variance. Classic symptoms.

YD

 

Have you replaced your lower control arm bushings in the front? If not I would suggest you do. With 70k miles on the clock and some of those being autocross and track I would guess you probably need to replace the bushings.

 

Yup. Get a set of powerflex bushings for the front lower control arms. Other symptoms are severe tramlining on uneven surfaces, and instability at speed when the road is wet.

Shaking steering wheel could also be warped rotors. Most MINI rotors cannot be turned. They need to be replaced after every pad change.

 

good suggestion guys I didn't think of that. Is there any way to test them to see if they are shot? Seems to me they would be a good "upgrade" regardless.

 

If you can get it on a lift or otherwise off the ground so you can see the bushings you might be able to see the problem. But the way they are attached to the sub-frame makes that a little difficult. The way they are usually diagnosed is up on a lift with a pry bar wiggling the control arm and checking the movement.

 

Have you looked at the wheel bearings? If you can grab the top and bottom of the tire while the car is jacked up, and it has play in it (pulling/pushing perpendicular to the tire) it may be the bearings.

Whatever you discover, please pass that on to us. Hope you fine the problem soon!

 

Mid-'80s era 5-Series BMWs were bad about this... funny that BMW makes MINIs and you're having the same problem... not funny for you, I understand.

On those BMWs you could replace everything over and over and still the problem persisted.... something in the design of the front-end? Who knows.

I went through it with 3 different 5-Series... the only thing that ever worked was to put bigger brakes on it... from a 7-Series! It worked, and it worked well.

Maybe there's an answer for you out there somewhere.

 

First - thanks for the input folks. Here are my next steps. Replace the rubber brake guide pin bushings with brass, replace the brake cylinder rubber parts and replace the braided hoses. Not that i think any of these will work but i have the parts, I can do them quickly and easily myself and they are good things to do anyway. I am going to replace the lower control arm rear bushings as soon as i can afford it. Also I will test the bearings tonight. That will basically leave the inner ball joints (big job, mucho $), the wheel hubs/bearings, a DSC control issue or the stearing system itself so I'm running out of bits to replace.

Any one got a new front suspension they want to sell?

I will keep this post up to date when I get the work done.

 

If you have a pry bar simply trying to pry the control arm will tell you if they're shot or not. They should be plyable but not soft. If you're able to move the control arm freely with little effort they're shot.

FYI: I'd suggest a lift for the above procedure, not sure I'd be under my car on jack stands applying significant amounts of pressure. At the very least get a set of Rhino Ramps.