Steering Vibration

[Ian Bowers]

Okay, so I've tried to fix this by myself, but I'm finally asking for help.

Right around 70MPH, the steering wheel vibrates back and forth. The vibration cannot be felt through the floorboard, gas/brake/clutch pedal, seat, or shifter.

The vibration isn't consistent, however. It depends on road surface. I drive a 20 mile stretch every other day, and it vibrates over the road sometimes, and others it doesn't.

It started after I had the car on jackstands for around 1.5 months. I put the car down, and the steering vibration was immediate and evident. While the car was on jackstands, I did unbolt the steering rack from the subframe to put in better spacers (Z3 rack), and shimmed the EJKnight skidplate down. The head was off the car, but I don't think that would change it.

so far, I have done this list of things:

Rotated tires from front to back, no change
Alignment, no change
Tried the old steering rack spacers, no change
Tightened the 32mm nut on the steering column, no change
Took my strut bar off, no change
Put strut bar back on, no change
Took steering wheel off/put back on, no change

I know the tires don't have any flat spots, they were put on in May, DZ101 star specs. The wheels MAY be bent, I did knock a good pothole minutes before the car was put on jackstands. But, I was hoping moving the rear wheels to the front would show if it was that.

It's fucking annoying the shit out of me, as it makes my arms go dead after a 2 hour drive. The one thing I still have to do is get the tires re-balanced and see if it changes it.

All of the front end was rebuilt 10-15k miles ago. GC coils, new LCAs, rack, tie-rods, CA bushings, GC camber plates. The only "old" part on the front end is the steering rack guibo.

Any suggestions? comments? trolls?

Thanks in advance,
Ian

[bernzpeed]

i had this problem and replaced the control arms ball joint, end links, and control arm bushings. it rides better now and no vibration. I used to get the vibration on 60 and 80 mph. are yours in good order or needing replacement?

xtn

[Ian Bowers]

Mine are nearly new, they're less than a year old. Very good order.

[jlevie]

How old are the shocks?

[bernzpeed]

Torque on wheel nuts?

Sent from my HERO200 using Tapatalk

[Ian Bowers]

How old are the shocks?

Shocks were replaced with everything else last year, less than 15k on them. Koni SAs.

Torque on wheel nuts?

Sent from my HERO200 using Tapatalk

Not sure on specific torque, I just tightened them with my breaker bar, like I've always done. I'll pop them off and torque them tomorrow, 70ftlb?

[tonywonder]

I posted this in the cannot diagnose vibration thread. I've had a similar issue and it was my mastercylinder. It was applying the brakes and it was only noticeable at high speeds. Check that. After ruling out the wheels ofcourse.

[Ian Bowers]

I will check that after I get the wheels re-balanced. Thanks for the heads up.

[Ian Bowers]

Wheels were balanced today, still no change. Anyone have any ideas before I replace the master cylinder?

[Ian Bowers]

Small update, vibration is getting worse, now showing itself from around 50+, strengthening with speed. Wheels balanced out fine. I'll be changing the MC, but I'm at a loss on what else to do.

Thanks if you have any ideas,
Ian

[tonywonder]

before u change it check thats the issue. what do ur pads and rotors look like? check them. if they are still good how long have you had those pads? it might not be the master.

the way we found out on my car was we had the rotors changed and pads and that was when it started showing itself. we put the car up and noticed that the wheels didnt turn freely. it was the same with the brakes applied and not applied. so check that before u change it.

[Jaxx_]

fwiw, I've heard of people getting wheels that are out of round and having an unfixable phantom vibration. Apparently more than 2mm runout can cause it.

[Ian Bowers]

before u change it check thats the issue. what do ur pads and rotors look like? check them. if they are still good how long have you had those pads? it might not be the master.

the way we found out on my car was we had the rotors changed and pads and that was when it started showing itself. we put the car up and noticed that the wheels didnt turn freely. it was the same with the brakes applied and not applied. so check that before u change it.

I just put new pads on yesterday. Rotors are fine, near their replacement time, though. The wheels do turn freely, no drags or anything.

fwiw, I've heard of people getting wheels that are out of round and having an unfixable phantom vibration. Apparently more than 2mm runout can cause it.

Hmm. Did the wheels still balance out? They are cheap XXR wheels, so I wouldn't be too surprised if that was the case.

Thanks for the input, guys.

[tonywonder]

i would rule out the MC then unless u end up noticing crazy wear on them. are your bearings good? maybe try using another set of balanced wheels to check if it still happens?

[Ian Bowers]

i would rule out the MC then unless u end up noticing crazy wear on them. are your bearings good? maybe try using another set of balanced wheels to check if it still happens?

The wear is very uniform and even, so, eh. The bearings (as far as I know) are original, but they may have been replaced. There is no bearing noise, they spin smooth, and there is no slop at the front (or rear) wheels.