Very strange vibration I cannot pinpoint...

[Sean]

So - riddle me this everyone.

My suspension has about 45k on it. Control arms, THR Eyeball arms, strut mounts, tie rods, Subframe bushings, TA Bushings. It has been SOLID as a ROCK the whole time. Not as much as a single tiny little vibration. Brakes have less than 4k on them and that's definitely not the cause as it has nothing to do with braking. Tires were rebalanced and that removed some of the vibrations, but it's still there.

As of about 2 months ago, I'm getting vibrations in my steering wheel that I SORT OF feel in my feet. Definitely a front vibration. When lifted, the wheels do not budge - bushings seem to be solid still. However, when driving, my wheel shakes slightly. The severity can vary - I'll start driving and it's really bad. I'll stop at a light, start going again, and it's not AS bad.

Also - and this one really gets me - when I first turn is seems to vibrate worse than when the car is going straight. Like, when I apply load to the steering knuckle is when the vibration is felt more through the wheel.

Here's my thoughts:
- My THR Eyeball arms are real rusty - maybe I should pull them off and refinish them?
- My CAs are on their way out - maybe I should replace them?
- The rubber steering knuckle that I modified for my Z3 2.7i rack is worn out and allowing the steering shaft to vibration is relation to the steering rack (new rubber damper) - or I can replace with the aluminum one that I've left sitting for years haha
- Tie rods are on their way out and I should replace them

I'm leaning towards the steering knuckle rubber damper. Thoughts???????

Thanks!!

[bernzpeed]

maybe the rubber disc on the steering knuckle?

[Stoner Sam23]

drive shaft out of balance? just one of my current problems

[Sean]

Not driveshaft. Not RPM dependant.

I'm leaning towards the rubber disc on the knuckle. Wondering if anyone has had the same vibration and if that fixed it.

[urbancynic]

How old are your tires? Is the tire pressure correct?

[Stoner Sam23]

does it change with hard accel or breaking? are we talking parking lot speeds?

[b*saint]

Bent wheels if the oscillation is getting worse then getting better AS you drive.

[Sean]

It's nothing to do with tires or wheels. Has nothing to do with acceleration.

- Happens at all speeds - car has been SHUT OFF and it still occurs. (aka: reiterate: not driveshaft related - wouldn't shake wheel anyway)
- Wheels were balanced on a road force only about a month ago - no bends in any of them (they are 15" - too much tire to bend probably)
- Tires are almost brand new (mounted last July)
- Tire pressures will have NO AFFECT on vibration (really?? LOL)
- Reiterate: Brakes have no affect on this vibration...

Sam, it doesn't usually start happening until about 45 - and then it's felt at random severity above that speed

[jlevie]

It sounds like tires to me. Swap the front wheels to the back and see if the symptoms change.

[b*saint]

I would also get rid of that rubber steering knuckle haha. Rubber steering knuckle - what a joker.

[Sean]

I would also get rid of that rubber steering knuckle haha. Rubber steering knuckle - what a joker.

Replace with aluminum?

Already swapped front rear before balancing a month ago. They have been balanced and tested for bends less than a month ago. That is not the problem. BUT - I suppose it wouldn't hurt to swap them again at this point. haha ;)

[b*saint]

Yea but you can hit a pot hole leaving the tire shop the day you had them tested and bend them.

[Sean]

True. But it was there the second I put them back on when home.

Also, these wheels have been used since 2004. Driven thousands of miles and not a single bend. Track record would tell me they are not bent. 15" wheels with 50 profile sidewalls helps.

[b*saint]

It was there the second you left but not before? The wheel place did something wrong.

[Sean]

It was there the second you left but not before? The wheel place did something wrong.

Ok...umm. Not sure how to put this.

The FIRST vibration was definitely wheels. I swapped front to rear the the vibs moved locations. I had them balance them all - all were off barely an ounce. After that, the nasty vibrations were gone. However, I now had a smaller, less noticable vibration - that only occurs up front and and random severity.