OK. This is my last time trying to figure out what the hell is causing this. I'm on GC/Koni for two years now (50k miles), and it's been doing this ever since I installed the suspension.
From 0-10 no shimmy
From 10-20 no shimmy
From 20-30 I get shimmies
then around 70, i get a slight shimmy, with it going away around 75-80mph. Don't normally drive that fast but I was just trying to figure out if it would do it up there.
I've checked the following:
Mounts = GOOD
All nuts n bolts = GOOD
Struts = GOOD
Coils = GOOD
Alignment = GOOD
Balancing = GOOD
I have a slight feeling that it may be a warped rotor causing the vibration, however those are only 1.5 years old and I don't feel any major pulsing in the brake pedal. I also don't think it's the wheel bearings because there is no play in the wheel when off the ground whatsoever. Could it be the engine mounts? My engine moves like a good 2" when the car is in park and off the ground, and I try to move the wheel. (PIcture that it makes sense) Is that normal?
Anyways, I don't think its a huge safety issue because I've been passing inspection every year, plus nothing has like...broken? I don't know. Suggestions?
Vice President - NEJBody
2007 Cobalt SS
2001 Sunfire (retired)
Which direction does the engine move? Up/down or rotationally? I can't recall ever seeing an engine move that much (besides the time I had a broken mount on my old Sable, and the engine kept hitting the hood
)
front to back or vice versa
Vice President - NEJBody
2007 Cobalt SS
2001 Sunfire (retired)
Thats a weird one. I would say imbalance, but you'll only feel that around 50-60mph, and you checked it anyways. Is it really bad at low speed, like you can see the wheel move, or do you just feel it? You'd have to have some serious runout on a rotor to feel anything more than a pulsating brake pedal.
Shimmies..you mean the car shaking, like someones pushing the side of the car kinda feeling. Have you checked your rear wheels, had a clients car once that it felt like the car was riding on an oval wheel in the rear. At a certain low speed it would shake you side to side a bit(not much but one of those wtf feelings)..and at higher speeds it would cause a vibration..but slight because of it being in the rear. The fault what the rh rear wheel warped, not the tire but the mag itself. But Ican also see it caused by a bad tire also.
Ne-waz long story short, have you try'd rotating the wheels. I know this has only happened after your suspension install. But you'd have to remove the wheels to do so..and they might have been mounted differently, which in the end makes the shimming. Or you could of hit something sideways like a curb..i dunno, but i'm sure you get the picture
ive rotated tires about 4 times since the suspension install, and it never went away. although, i do have shims installed in the rear to supposedly correct my alignment. had that done like 2 years ago too. but it did the shimmy before the shims and shimmied after. i dunno. i guess i will live with it.
also, if i floor the gas pedal...i dont feel the shimmy. but with normal acceleration its there.
Vice President - NEJBody
2007 Cobalt SS
2001 Sunfire (retired)
Broken belt in tire? Hub centric rings? Or balancing of wheels. I took my car to get the 17's balance twice at a dealership. Still had a little vibe at 70. So went to another place to get them balanced and all fixed. Just throwing ideas out there.
Not to thread jack, but how you like the ride otherwise. I just got my GC Coilovers and am saving for some Koni's.
Ride quality is great. Sure, the springs are a bit stiff and you feel every crack in the road but the rebound is great. I drive alot, around 450mi/wk and its not punishing. I can out handle 90% of the cars on the road with the 17s. Go for that setup, wont be disappointed. I have the reds not the yellows though.
Side note: I've replaced two of the four tires originally on the car since I installed the suspension. Wheels are steelies right now, and I still get the vibe so hubcentric rings cant be doing it. I had my alignment checked at three different town fair tire locations, all good. sears did my balancing, and i watched the machine spin em true. So, it's not that either. Belts are fine.
Vice President - NEJBody
2007 Cobalt SS
2001 Sunfire (retired)
try returning the suspension to stock and see if it does that. If it dont, then its something with the suspension, although im not sure what. I know someone is going to say that this isnt needed but ive done it before on a lot of cars to pinpoint problems.
2004 Cavalier, 2.2L Ecotec
1965 El Camino, 396 BBC, 14:1, 800 BHP
If it goes away under hard accel, and the motor moves around alot, replace the mounts. They're pretty cheap, and if it doesn't go away, what have you lost?
i think i'll do the mounts, theyre pretty much shot but not to the point of the motor hitting my hood yet
stock suspension isn't an option, its all in the junkers about 55000 miles ago
Vice President - NEJBody
2007 Cobalt SS
2001 Sunfire (retired)
