my car also has the shakes between 50mph - 60mph, if I go below 50 or above 60mph it goes away.

 

mine does this aswell

 

maybe i am not noticing the vibes in the wheel cause i have a zzp poly motor mount and the vibes are already there.

 

I had Ground Control coilovers/Koni's on my old car and when I lowered it, it did the same slight shimmy. When I raised it incremently, the shimmy went away by that much each time. GM should've designed their cars with a lower ride height from the get-go.

 

............. ur axles are at a different angle than what they were designed to be at, thats why you have a shimmy. you need to fab up some metal spacers and raise your motor back up to stock ish hight, that will eliminate this problem......... impala and grand prix guys have been doing this for years.

 

edit: ^^^you beat me too it!


my car is lowered 3.5 inches and i have this problem at wot, but only very little. the only thing you could do is raise up the tranny the same amount you lowered your car so the axles would be the same angle. too much work though. like i said mine is minimal

 

has anyone raised their tranny and had any success? I have the H&R's and i have been trying everything and nothing seems to work.

 

you could try loosening all you mounts at the same time and see if the engine and trans relocate them selves. it might help.

 

I installed KSport coilovers and the vibration went away completely.now I am lower than when I had the Eibach sportlines and no vibration, so it worked out perfectly.

 

I just put some CA1 springs on my car and got the same vibration afterwards. I dunno about you guys, but I can feel that it is definitely in the rear of the car. I got to thinking about it, and I checked out the springs today to see what they looked like under load. Well, they are almost 100% coil bound and I'm thinking that they compress and ride on the bumpstops under acceleration (my problem is the same as everyone's.. 1st and 2nd WOT wiggle). Could some people post what their rear Eibach's look like installed? Up until reading this thread, my idea was to upgrade to a "better" spring, but if this affects almost all lowered cars...

 

To me it seems like 100% that it is coming from the front of the car. The springs are not compress enough to be running on the bumpstops, at least mine arent, but I cut mine down as per Eibach's directions.

 

Now that I've been driving it for a few days, I agree with you guys that its all over and not just in the rear. That sucks that the aftermarket for shocks/struts is so limited. I can't stand the vibration, I'm taking these springs off. Anybody want some CA1s?

 

Mine has the same problem, I installed the Sportlines and Koni's the same day. Granted I havn't gotten an alignment but it doesn't seem that far off. Also I am leaking bearing grease from the CV boot by the wheel.

 

I have also had a slight shimmy ever since I installed my SSC springs back in May. Strangely, the vibration was reduced significantly when I put in my Corbeau seats! It comes back when I have passengers though. It definately has to do with the drive shaft to hub angles. The only confusing part is, that my camber was within GM specs for the front and only my caster was right at the limit. It does not make sense that there would be so much vibration if the wheel alignment is within spec! Maybe the angle problem is not at the hubs but at the axle?

 

I still have the vibration, and I think its even gotten a little worse. I had the car up on a drive-on rack and it is definitely the CV joint angles. With my springs, the axles are pointing a good 10 to 15 degrees upwards going from the transmission to the knuckle. I think the joints on the hub side are okay because those already undergo huge angle changes (turning) and are fine. I really think that it is a problem with the cv joints on the transmission side, specifically, the joint that goes into the intermediate shaft or jack shaft. Just wanted to share what I have seen so far. And +1 to the group of people who's alignment was perfect after lowering.

 

Check this out guys:

https://www.cobaltss.net/forums/suspension-67/ok-so-i-think-i-might-have-figured-out-lowering-springs-vibration-issue-84325/

 

exactly what i was about to say. The top of these struts are somewhat tapered and the strut cap has to be aligned properly to ensure that the spring sits flush on it. If not, you're going to feel vibration between the spring and the strut.

 

My problem was when I was runing Sportlines, due to the extreem lowering my front sway bar was then resting and rubbing on the lower control arm. I have a thread areound here from a few months ago about a vibration issue after the spring install.
https://www.cobaltss.net/forums/show...spring+install
Page 4, post #60
I changed everything, hubs/bearings, cv axles, breaks. My vibration was only at 20mph and when a made a hard left turn. So I sold the sportlines. But ordered the CA #1 springs, hoping that I wont run into the same problem, these springs have no where the drop of the sportlines. Keeping my fingers crossed.

 

old thread... but I have the same issue with my Sportlines.

I only notice it on smooth roads on low acceleration ~1500rpm... there is a slight shimmy up front. It is not felt in the steering wheel though. It is enough shimmy to rattle my water bottle though.

I took the GM tech out who installed them for a ride, and he said it was the angle change of the CV joints causing it. No real answer on a fix though.

 

it all has to do with the angle of the axels... they are binding and that is what you feel... I have the issue with mine as well but is very minimal... only under throttle 1 and 2

 

does this put alot of stress on the axles im on ssc and have the same problem in first and second low speed.
im afraid of blowing a cv joint from a dig

 

bump for help