It is also mind boggling that someone would post something like this without mentioning what that "single part" might be.

 

I suspect that boggling minds is just what he had on his mind....

 

I'm guessing this is his sarcastic or tongue-in-cheek reference to "the nut behind the wheel" joke….

 

Oh, I get it. Wish my problem were that simple.

 

So what are you going to do now? The usual suspects have all given you advice including some genius suggesting that the problem lies with the leaf springs.

 

Waiting for the dealer to acquire a Digital Angle Gauge and Adaptor to check the rear caster measurement.

 

I'm interested in 2014 C7 but experience has taught me to let the first year of a major redesign go by and let Chevy fix the nagging little problems uncovered by owners driving on real streets. handling is not much for this car not unless you modify the suspension.

 

Really? Not my experience.

 

 

JSibert, I am having the same exact issue that you have described but with a std C7. I have not lowered the vehicle and have had the alignment checked twice. I have had 3 BMW Z4 that had to be changed to non runflats to eliminate this issue. I have also had 2 C6 and did not have to change to non runflats because they handled great. This car is just plain scary the way it handles. If the road has any hint of grooves I can't pass another car because it rocks back and forth too much. Going over a bridge or dip in the road it shifts right and then back to the left. This problem is worse at 70 Mph and I'm afraid to drive it faster in those conditions. My wife doesn't want to ride in it because the back and forth motion is making her sick and scared.
My local dealer doesn't know what to do with it and so I'm scheduled to go to a larger dealer that sells Corvettes. They said that they haven't heard of this so I'm not looking forward to explaining all this and knowing that they will think it's just me.
One other issue that I don't think is related but worth mentioning... there is a subtle vibration that comes and goes on a regular basis. It is only detectable on smooth roads, any bumps or cracks in the road distract enough so it's not noticeable. I have had the tires balanced a couple times and the last was on a road force balancer (if this is the correct name for it). It was determined that one tire was out of spec and was replaced. Unfortunately this didn't correct the problem. Not sure what is going on with this.
I have searched other parts of this forum but couldn't find anyone with the same issue. Finally someone else has this problem (sorry it's you). Have been considering seling the car because of this. Do you have any answers yet? Thanks!

 

I believe there is a recall on rear shocks with cracked mounts (the shock itself) on the base car.

If you are experiencing vibration on smooth roads and swaying and awkward movement, check the shocks

https://www.corvetteforum.com/articl...ock-absorbers/

 

I said that it could only be one thing.

 

I found that Jsibert started another thread and his problem was corrected when the jack caster was adjusted.
I have had the car at a dealership working on the vibration over the last few weeks. they were speaking to GM and were directed to check the tires on the balancer that found a tire out of spec. Would it be safe to assume that the VIN would have been checked for recalls and the shock issue?
Shaka, you say it can be only one thing. Care to elaborate for someone that isn't making the connection? Thanks

 

I also had the same problem with bump steer and what felt like a 'loose' suspension. A friend who used to race cars for a living told me to throw out the run flats and buy a set of Michelin Super Sport Cup tires, which are a very soft rubber compound without the stiff side walls. Guess what? My C7 now handles like a completely different car, and I wouldn't have believed it since no one seems to complain about run flats. Evidently, the thick side walls do not "give" enough for the car to absorb the bumps, so you're thrown sideways after hitting a bump or going into the rain grooves. The really soft rubber of the Cup tires allows your car to stick to the road, beyond your expectation. That is why real track cars use this tire. However, there are two draw backs:
1. They have a treadwear rating of 200, which is about 12,000 miles of driving. One hard day at the track can scrub these down to the steel cords, but you can't really track a car on run flats anyway.
2. You will need to carry the flat tire repair kit in your trunk pocket. It doesn't look too hard to repair a hole in the tread, but of course, if you pop the side wall, you'll have to call a tow truck. Do not let that stop you from buying these tires! A set of 4 in the Corvette offset costs around $2,200 here in Los Angeles, and most of the time, they're special order. I forgot to mention that these are also a couple of pounds lighter, meaning that the car will respond better.

 

Thanks for the info. Seems like I should confirm alignment first and then correct the vibration that I mentioned as well. If these issues aren't corrected new tires will be the next step.

 

I disagree. I had the OE run flats on my C5 and it handled great. When I replaced them with Michelin run flats, the car still handled great. I had the OE run flats on my C6 Z06 and I never experienced any stability problems the OP is having. I changed the OE Goodyear's for a set of Bridgestone run flats and the handling of the car is still exceptional. I've had it over 145 on a rough road; Z06 was moving around, but the road was rough(as it was built in the 1930's and hasn't been repaved in many a year, but I had full control of the car with no problems the OP is experiencing), and over 160 on a smooth track(Talladega).



Take a look at the videos of GM running the C6 Z06 and ZR1 around Nurburgring. Do they look like they are out of control at speeds of 160 -180 and that track is not a super smooth track. Oh, and run flats are on the Z06 and the ZR1 in the videos. The Cup tires GM used on the C6 ZR1 and the C6 Z06/Z07 and the new C7 Z06/Z07 are also run flats.

 

Had a similar issue with a Miata one time. Put new tires on the car and it would dart all over the place. Pressures were correct, and no visible issue with the tires.

Dealer contacted the manufacturer, they replaced the tires and the problem was solved. Tires were sent back to the manufacturer for evaluation, but I never heard anything back.

Don't rule out the tires.

 

The camber on the images, is whacked. The front should be equal and negative. -0.5 degree is a reasonable handling setup for the street.
AutoX or Track, as negative as you can get (-1.5 to -2.5 or more depending on how fast you're going) , depending on your wallet.
The rear, where your problem is even worse, they should both be negative, normally the rear is a little more positive than the front, (but still negative). Most of the race setups the fronts are 0.5 - 1.0 more negative. The real check is tire surface temp, even surface temps at speed on the track.
iirc my C5 Z06 was like -1.1 f and -0.7(-0.5?)in the rear. The cross camber in the rear is the first thing I'd fix.

When I lowered my Z, I worked really hard to make sure it was level, as that controls weight jacking (which I think was mentioned up thread), I was going to get it weighted on a set of scales, but never did.

 

The car is aligned to move slightly towards the right at the rear and to move slightly towards the left at the front. So when yo take an up bump, the car is going to want to rotate counterclockwise.

While the readings are within spec, what you want is both side to have the same reading; +/- 0.1 maximum tolerable difference.

Oh, and BTW, there is a big difference between having no specification for caster and having a specification of 0.0 degrees for the caster specification. The former says that any reading is within spec, the later says that only when the caster is 0.0 is the specification being satisfied.

 

I'm guessing Shaka is trying not to say it must be shocks.