Before I begin, I'm still a newb at repairs and this was my first attempt at a lower control arm replacement, so forgive me for any improper terminology or vague wording but I'll do my best.

Long story short here ... I needed my lower control arms replaced and I took it upon myself to do the driver-side LCA, let the mechanics change the passenger-side LCA because the bolt was seized and I didn't want to deal with it.

This was my first attempt at a LCA replacement. I knew I had to torque the bolts with the wheels on the ground, but seeing as I don't have a hoist I figured it would be ok to measure the distance from the center of the hub-cap (with the wheel on the ground) to the wheel arch above, then jack the rotor up until the center was the same distance to the wheel arch as my previous measurement.

So, the lower control arm was definitely raised, not quite level with the ground or anything, but it was raised a fair distance - the distance I thought it should be based on my measurement, and after taking the car for a drive everything seemed great. For about a week, then it started clunking again, louder than before and more frequently than before (with the old control arm).

Still is clunking (it's now been about a month and the passenger-side LCA was replaced 4 weeks after the driver-side, note that I avoided driving as much as possible/used the work truck during this period but I think that first week where I drove my cobalt might've done 'er in).

So obviously I think my new bushing has gone bad even though the mechanic told me (while replacing the passenger-side one) that the driver-side LCA is fine and the clunks were just because I only had one new LCA installed at the time. Inspecting the bushing area today, it looks good, lots of space in there, can see the bushing clearly, looks just like the passenger-side does. Yet it clunks hard when I do a sharp left turn or accelerate quickly.

My question is what do you think I did wrong? How can I avoid this in the future and am I correct in thinking that the bushing has already gone bad?

 

It's possible it's not the LCA. My clunk was sway bar bushings. Other sources are sway bar end links and steering intermediate shaft.

 

Would either of those cause it to clunk when accelerating, braking, and sharp turns at low speed? That's when I hear it clunk and I can feel it in my left foot under where the brake is. It's quite loud and powerful sometimes.

 

Yes, yes, and yes. Since you have new bushings in the control arms, the subframe is much tighter now, which leaves the end links as exninja said. The other thing you could be hearing is the intermediate shaft (the u-joint rusts out pending climate) or your front sway bar bushings... or since it's a cobalt: all the above. I would start with the end links though, as it's $50 for the pair (Moog are good) and if you get the ones that have the nipple, you can grease them after some time (again, pending climate) and is the easiest fix.