Here ya go, K-spaz. These all came up with C5 forum search for "turn steer pop hop". There are more.

http://forums.corvetteforum.com/c5-t...nt-wheels.html

http://forums.corvetteforum.com/c5-z...e-turning.html

In this thread, the OP has a problem in the rear but a couple other people go on to describe the same front wheel turning behavior

http://forums.corvetteforum.com/c5-z...ght-turns.html


Also do yourself a favor and read up on this...
http://en.wikipedia.org/wiki/Ackerma...ering_geometry

The root cause is the fact that the inner wheel is being forced into a radius that's tighter than its hub orientation would naturally dictate. Hence it *pops* or rather slips and sticks when you have wide, sticky tires. Again, most cars don't exhibit this behavior because they have relatively low traction and the tires will scrub (slide) easily.


So uhmmm, you ready to rethink this statement yet?

 

Sorry, no I am not. Ok, there's more than one person with the issue, that doesn't make it "normal".

I have Eagle F1's on my car. "Super Sticky"? I'd say nothing like Dulop's or Pirelli's, certainly not Nittos. But... Sticky enough for this phenomenon to occur if the car is setup wrong? certainly.

I have had a car without the problem, then the car got the problem, then I resolved the problem. What part of that are you guys missing? If this guys not happy about "the problem", it's fixable. Ok, are you guys ready to 'rethink' that yet?

PS. Sounds to me from your quotes above that most of those people think it to be a problem, but simply brush it off and really don't give a $$(% about it. And I suppose if enough people say forget about it, they will. Wonderful.

 

Oh I see, so I clearly prove you wrong with your blanketing statement so you back-peddle. Roger that.

Which part of it's a normal thing and not a problem are you missing? It's not a problem. Q.E.D. It happens to every car out there. every single one. There are just certain conditions that can and will exaggerate that effect such as running wide, high-traction rubber.

You're basing your entire argument around the fact that YOU got ONE bad alignment job. What happened in your case is the toe probably got set way out of whack. And the toe setting has a direct effect on how the hub articulates while steering now doesn't it? So it has the potential to cause a greater angle delta between the two hubs, right? HMMMMM ... that picture starting to come together for you yet?

The inner tire is going to scrub. Period. Nothing you say or do will change that. No amount of denial will change that. It would appear that you're not really the self-educating type, but I challenge to you read the wiki article I linked on Ackerman steering. It really is quite informative, and spells out for you exactly why and how this happens.

but I already know you won't read it

 

Wow, cool! Got some conversation going. Unfortunately, they didn't give me the alignment specs when I headed out the door so I can't tell you where I'm at. Yes, the hopping, or whatever it is did it very mildly before the alignment, but much more drastically afterwards which is why I started this thread. And the tires are Michelin Pilot Sports, which in my personal 140k mile experience are way better than the Goodyear runflats I used to changed out every two years. Go to TireRack.com and do a comparison and believe everything you read about the Michelins. Anyway, the place I went to (and by the way it was a Goodyear shop owned by a friend of mine) that did the alignment and then gave me the previous story about the diff fluid wanted $125 bucks to drain 2 quarts of oil and replace it. So I'm really suspect about what they are telling me. Who charges $125 bucks to drain a read end??? Here's what I'm going to do. I'm going to do the 75w90 swap out and if that doesn't take care of it, I'm going to a place some of the local vette club guys have recommended and have the alignment checked again. I already blew $100 bucks on the first alignment but now I'm pissed enough to have it checked. So like Paul Harvey ... stay tuned for the rest of the story.

 

My 01 also does this hop or ?? when backing out of the driveway and turning sharply. I had the alignment done, since I lowered the ride height. Still did the same thing until I put the stock wheels on with stock sized tires and it stopped. I run 18x9.5 wheels on front with 255/40 BFGs normally but switch back to stock for winter and that is the only change between feeling that problem and not. I have to agree that tire size (traction ability) makes the difference on mine.

 

That's too bad you didn't get the alignment numbers. Without them, there's no way of knowing if they aligned it properly or not.

 

So the hopping stopped when you reduced your front traction.

fascinating

 

Changed the diff fluid last weekend. Only charged myself $75 bucks! Had a 50% off coupon. Wheel hop still there. I'm calling BS on the limited slip cause. Going to find a REPUTABLE alignment shop, but may be a while though. Will update here when I get that done.

Thanks, everyone

 

you know it's relatively simple to do your own alignments, too. it's way less inconvenient than the rear end fluid you did. once you learn how to do them, the next time your friend mentions he had his car aligned, go check a set of wheels. ive seen about half of my friend/family's cars come back slightly off. not so much that it's out of spec, but it could certainly be done better. the notion that a shop could be way off is extremely easy to believe. if they dont get their machines calibrated or do it by hand, it's a rough approximation at best.

between that fact and having 5+ cars at any given moment, i bought my own tools and learned. i wouldnt let anybody touch my cars after doing this

 

I posted a thread with the same condition. My 03 Z06 has the same malady! When backing out of a parking space and turning the wheel to the left it makes a grinding noise like the wheel is hitting the fender and jumps a bit like as you say running over a walnut or rock. My car still has the original tires on the front and they are not runflats. My car is also harder to steer than a regular C5 "I had 2 others". No one seemed to have an answer in my thread so I guess that my next step is to put on new tires and get a alignment.

 

Is it really wheel hop? My wheels have clip on weights to balance them - yes, including in the back. Under certain conditions when the steering wheel is turned to lock, they hit the suspension.

 

One of the respondents was right this issue has been beat to death. My 2003 Z06 does the same thing when backing out of the garage and tuning the wheel most of the way. The first time I noticed it was in the winter backing out of a parking spot. I thought that the wheel was hitting the fender. Mine is still doing it.

However I noticed that it is only doing it when the car is cold. After driving for awhile it will not do it. As an example, I pulled out of my garage this morning and it did it. Played golf and pulled out of the parkin spot and it did it. When I got home I could turn the wheel either way and it did not do it. ps; My car only has 18K on it.

 

Had a teacher once tell me, "It's better to keep your mouth shut and let people think you're an idiot, than to open your mouth and remove all doubt."


You have no clue what you're talking about. Pick up a suspension design book or go ask a alignment/suspension expert.

 

check your front tie rod ends, my guess is one or both are in need of replacement.

good luck
john

 

Hmm. I haven't noticed this at all during the 8,000 miles in my Z. Stock tires or Vredesteins. Not cold, hot, wet, fast, slow.....
If I did or do I think it would make me crazy.

 

Well then you should have listened to your teacher.

 

I had the same popping on my 02. Getting ready to get the rear-end looked at. I already had a set of the Z06 shocks ordered and delivered. Went ahead and installed them. The damn popping went a way, and has never returned in two years. Go figure.

 

Definitely a suspension geometry thing! I have completely mod-ed my 98 C5 suspension over the years. Phat coil over shocks and springs, Hotchkiss sway bars, neoprene bushings, and front and rear bump steer kits. For tires, I have run everything from Hoosier autocross compounds on the track, run craps, Michelin PS2s and now a set of Bridgestone Potenza’s. The alignment of a C5 is much more than a normal shop can handle. The Corvette essentially has two front ends. Take your car to a shop that does racing set ups. I have had mine set up to where it pops and does not pop as I played and searched for the perfect alignment. Duh, there just isn't one LOL! I have watched other cars at the track and seen their tires jump when making tight turns in and around the pit area. There are any numbers of scenarios that can cause it both good and bad. If any alignment is out significantly of course it will shred the tires in no time in some cases you won’t have an indication until you check the tires.
In a nut shell when making a tight turn the inside tire must draw a much smaller arc than the outside tire. BUT! If the car was set up for a circle track the issue would be easy however on the street and road courses it becomes much more complex as you need to turn left and right. Ergo compromises in set up have to be made. I added the bump steer to lessen the compromises. People don’t realize as the car goes down the road the total toe of the front and rear change constantly as the car rises and falls on the suspension. Primarily because the tie rods do not pivot in the same plane as you’re A- arms the bump steer helps eliminate some of this, but it is a PITA to set up correctly.
To really help you out not only would we need to see the current alignment specs, but also what the ride height is front and rear. Otherwise we would be writing the encyclopedia to explain everything.

 

A I indicated earlier, I had exactly the same symptoms. It was especially bad when cold. I put new tires on my 03 Z06 last week and had a 4 wheel alignment done.

No more running over walnuts!!

My prognosis is that the front tires were below the wear indicator and were scrubbing when turning. They were OK when warmed up after about 10 miles. Last winter I drove to a Doctors appointment and really had to search for a good parking space. I had to turn the wheels quite a bit to get in the space just right. About an hour later when leaving, I cut the wheel to the left to back out and it sounded like the right front wheel was hitting the fender which it was not.

Try new tires!