Back from the dead! I continued to chase down this problem, while repairing/upgrading other bits. Did 4 C6Z shocks, a front leaf spring(wanted non seized adjusters), a driver side front wheel bearing and just this weekend, 2 OEM C5Z front wheels.


Got my current tires transferred onto these new wheels, they balanced beautifully according to the tech. Minimal weights and a roadforce rating of <10 for both. As I loaded up the old replicas, I noticed the "MADE IN CHINA" sticker on the inside of both barrels. This was my concern from the getgo. Replicas suck! My vibration is entirely gone, 60-80 is vibe free and smooth driving. I'm not quite sure if it was the balance job or the wheels themselves, not sure if they are able to be balanced sufficiently. Either way, I might keep them as spares or a winter set. The chrome is awful and peeling, and they're quite a bit heavier then OEM Speedlines. Now I just have to fix my clown car look, black replicas on the back, silver speedlines on the front.




SEE NEXT POST

 

Well I guess my pants are on fire, because this problem persists! It seems to be certain road conditions that excite this vibration. A certain highway I take everyday to work is smooth sailing, the next gets my wheel shaking! Normally I'd just blame the road and move on, but I can't imagine this is an acceptable level of vibration, even for hydraulic steering. 95 South from 32 to 495 is my problem road if any locals happen to read.


So once again I'm in other ideas mode.


First, a list of things I've changed since the creation of this thread.

• Front rotors and pads
• Outer Tie rod Ends (MOOG)
• Alignment
• Front Endlinks replaced(MOOG)
• Tires shaved and balanced, spun on car by the pros at Radial Tire in Silver Spring MD, great shop, treated me like king!

Alas, problem persists on a bunch of different roads, at speeds 60MPH+.


My questions are:

• Any way to check inner tie rod play? I realize they don't wear near as fast as outers, but should they not flop to the ground when disconnected from the steering knuckle? I was surprised to find that my tie rods easily popped off the knuckle just as the nut came off. On my BMW those suckers took a helluva lotta effort to separate. The rack boots are a bit damp on both inner tie rods, indicative of a rack seal leak, would that ruin an inner tie rod?
• Ball joints! I've shaken the wheels a whole bunch of times and have not found any discernible play involving ball joints. Should the car be loaded to test for play on ball joints? All my tests were wheels up, no load on the suspension. Occasionally do get a "thwump" sort of sound over rough pavement with the wheel turned.

Hope I get to come and post a real solution soon, open to any suggestions to get this thing steering beautifully. Harmonic Balancer install is scheduled for October, so the rack will be coming out soon, would rather not have it rebuilt when it could be a simple suspension piece.

 

What SHOCKS are you running?

I installed C6 ZO6 shocks on 02 ZO6 and I was amazed at the improvement in handling. Especially on rough roads.

Maybe shocks are in your future......

BC

 

C6 ZO6 shocks.

 

Sometimes it is hard to tell if a ball joint is bad until it gets real bad.

One of the holes where the ball joints or tie rods fits into the knuckle could be wallowed out. Its aluminum. Make sure none of the nuts came loose.

 

Third thread revival is the charm. I think I might be putting an end to this mystery. I've dealt with this issue since I got the car, threw a lot of parts at it, some worthwhile, some needless. Can't stress how important it is to really really inspect every part of a front end. I have no experience with double wishbones suspension, so I seem to have glossed over my lower control arm bushings. I knew to inspect the uppers, but alas, the lowers are hopefully where my issue resides.


Check this picture out!







Now that doesn't look right, does it? Anyways, that's the worst looking bushing of the lot, one rear looks fine, but the other 2 are also very suspect. A prybar revealed quite a lot of deflection when pressure was applied. I believe I've found my issue, could have resolved this months ago with a little bit of patience and a keen eye. I understand this happens under hard acceleration and deceleration as the car frame wants to slide forward and back within the bushing. I believe at higher speeds, the speed of the deflection in the bushings increases, giving me slight, but noticeable feedback through the wheel.



Now I'm shopping for either used LCA's, or buying a bushing kit and tackling the install on those. Anyone have suggestions for which way to go? Mild auto-x but mostly street car, I'm hesistant to go used as the bushings will likely do the same thing again. The ease of install of new arms is appealing though.


That's my update, will update again once I get this fixed. Still enjoy the car, but this issue was nagging at me for more then a year now, and I'm not defeated yet!

 

What did your issue end up being? Having similar issues on my 04 Z06.