-Eric-

So like the title says I am currently and have been experiencing steering issues ever since I bought my car from Criswell Chevrolet. I have had the car there and back 3 times now and I'm really no closer to a solution.

To their credit, they have done a good job in aligning the car, even if it took a few tries. The car came from the factory with the steering wheel 3 degrees off center and the 4 wheels pointed god knows where. At least the car is properly aligned now. Unfortunately, to get the car to drive straight we had to adjust the left side front caster 0.3 degrees lower than the right. I just took the car back this week for some adjustments to the alignment for wear and better performance and Criswell did a VERY good job with the alignment.

The trouble is the steering is VERY inconsistent. Not to mention that any imperfection in the road seems to pull the steering wheel in its direction. Sometimes even on brand new smooth pavement, the car starts wanting to go left then right then left and so on. Now I would almost write that off as wide sticky tires on nasty roads, but I've driven a 2013 427 vert with the same size tires and that car didn't do it. Now I know that car has hydraulic power steering, but I can't imagine EPS makes the car feel broken?

Last night I lifted the front end and checked the wheels because it just felt like something in the suspension was moving in ways it shouldn't. I couldn't find anything that was loose to the touch, but that doesn't necessarily mean that everything is right and tight.

The weird thing is on my way back from the dealer last time, 45 minutes away from me, the car felt solid and like it was going down the road straight and true. No problems. Then with about 1/4 of the trip left it was like flipping a light switch and the car was back to its old self.

I tried unplugging the EPS and driving the car without power steering. The issue remains, so I guess it's not the power steering.

I really don't think the car is behaving properly, but without the dealer agreeing and without the ability to drive another C7 ZO6 to compare it's hard to say for sure.

I would love to get some input from other C7 ZO6 owners on how their cars steer and generally go down the road.

gve

Mine wants to pull which ever way he road is crowned, and on some highways it goes back and forth. It's the tires but maybe your is worse then what mine does.

-Eric-

Thanks for the feedback! I appreciate it.

spearfish25

Mine is a wanderer too. Definitely the tires.

ramtip

I get a little bit of tramlining -- mostly on the grooved portions on some highways. Also am aware of road crowning more.

Here's an interesting read from Tirerack on the subject: http://www.tirerack.com/tires/tirete....jsp?techid=47
It would indicate that it will worsen with treadwear and higher tire pressures. The pressure may help explain why your trip got worse at the end when the tire temps rise. There's also some tips regarding toe settings and negative camber to help.

Sunny_M3

My car is the same, the steering wheel doesn't 100% center even though the car has been aligned. Went back to the dealership a bunch. The first time was a legit problem with the steering rack, which was replaced. After the new rack was put in, the car was much much much better. Now what I think I am experiencing is normal Corvette steering inconsistencies; will continue to monitor though. I too am pretty sensitive to alignment and steering.

dar02081961

This isn't any where close to right.
While I commend your dealer for trying. Having too offset align one side of a new car is unacceptable and points to something being seriously wrong. Have the dealer call the GM tech guys and get the higher ups involved this is way outside of the norm.

Good luck

383vett

Happened to a buddies Z06. Changed the steering rack and everything ok.

capevettes

It's the tires. My Z06 does it and my Viper does it. It's the 335's following every little undulation in the road. If you're tracking and stopping straight on flat surfaces, there is probably nothing wrong with your car.

sammyv

OP I would like to see your current alignment specs?

Bill Dearborn

I do have one question. Originally when the steering wheel was pointed 3 degrees off center did the car drive straight when you took your hands off the steering wheel?

Bill

-Eric-

No, it definitely would pull right, even if only slightly (on any surface too, not just crowned roads or worn roads)

-Eric-

Believe it or not, after trying several different tire pressures I discovered that the tires seem to pull less if I run them well above the factory recommended pressure. Right now I have them at 36 psi all around and it has definitely improved the car's manners.

-Eric-

Here you go:

Front
Left -1.6 camber / 6.8 degrees caster / -0.03 degrees toe
Right -1.7 camber / 7.1 degrees caster / -0.03 degrees toe

Rear
Left -1.2 camber / 0.8 degrees caster / -0.03 degrees toe
Right -1.3 camber / 0.8 degrees caster / -0.03 degrees toe

Which is basically exactly what I asked for, or as close as can reasonably be done. FWIW the car feels more confident while cornering and doesn't feel any less stable in a straight line. I was wearing out the outside shoulder of my front tires on the factory alignment so the extra camber should help.


I would also point out that GM's own tech materials suggest that if a car has a pulling issue that adjusting cross caster and cross camber is OK once the other possible causes have been explored. None the less it concerns me when you have to take such measures with the car.


I have also noticed that the car behaves much better in TRACK mode than TOURING mode. But track mode would likely break your back over a long haul drive. I think part of the solution may be a DSC SPORT controller for the shocks so I can make SPORT mode just as hard as track but also tune the shock to soften for high-velocity compression to keep the ride comfort there.


THANKS EVERYONE!!!!

-Eric-

I hear you! Any little bit of a problem and it just drives ME NUTS

pkincy

You didn't mention which tires. My SC 2 ZPs make the car wander like a drunken sailor particularly when cold. Even on a butt smooth asphalt road which is my first mile or so. Once it warms up they are better. The MPSS ZPs are much better but still tramline but at least I have a chance of keeping it straight enough to not get pulled over for a sobriety check.

mikegaan

At the risk of asking a silly question, I assume the dealership checked/reset the steering to zero (software plug-in adjustment) after fooling with alignment, wheel position etc?

Bill Dearborn

The first question I have is the dealership following GM's lead on the signage of the toe settings. GM uses positive for toe in. It is clearly stated in their Service Manual. What your settings show is a negative sign for toe which in GM's parlance represents toe out which could cause all sorts of wandering front and rear.

Check to make sure you don't have toe out. GM's toe spec's with the track alignment are 0.05 toe in with a tolerance of +/- .2 degrees in the front and 0.05 toe in the rear with +/- .2 degrees. If the tires are indeed toed out that means your settings while within spec can encourage the wandering you are sensing. Especially in the rear.

Here are a couple of other things to think about if the toe is OK.

If camber is the cause of your pull, it will always pull to the side with more camber (from negative to positive). If your car has .5 degrees negative camber on one side and 1 degree negative camber on the other side it will pull to the .5 degree side (since -.5 is more than -1).

Camber may pull toward positive (more tilt in at the top) but caster will pull toward negative, or less caster.

Your left side camber and caster settings look like they would make the car pull to the left. But those differences are very small and I doubt you have much of an issue with them.

Toe in (or out, or both) can definitely make your steering wheel crooked when driving straight, but it almost never causes a pull.

Your toe readings are all the same so it shouldn't cause the steering wheel to be off. If rear toe was not the same on each side you would have a thrust angle affect which means the steering wheel would have to be turned for the car to go straight down the road all be it sideways. If it wasn't the same on the front the steering wheel would be turned but there wouldn't be a pull.

I suspect you should have the toe checked and adjusted to zero or a little toe in in the rear and a little toe in in the front. Use the terms toe in and toe out instead of positive and negative signs as there is no standard on which way it should be marked.

Bill

pkincy

And toe is not impossible to check in a level garage. Simply take a long tape measure and hook it to a specific tread on one tire and measure across the front of the tires to that same tread on the closer tire. Do the same on the back of the tire. You will not get within 0.0x in, but you will certainly learn if you have toe in or toe out. However make sure that you are measuring below any spot where the car itself can misalign the tape measure. I have toe plates that fit flat against the outside of the tires and have a cutout for the tape measure, but the tread block method works well enough to get a fix on whether you have a big problem or not.

golgi

I have this exact problem. At times, on the worst of rutted roads, the car tracks straight as an arrow. Same road, different time, it feels like it is literally pulling the steering wheel out of my hand to turn left or right. It will do the same thing on a nice freshly paved surface as well. I thought it was originally related to braking, but that doesn't seem to correlate.

This is driving me nuts, and my dealer isn't the greatest. I guess I'll give it a shot. I see a couple of people have had their racks replaced. Are there known issues?