Noise in front suspension...what could it be?

[MagikDraggin]

On my '04 coupe (27k miles), there is a sound which is reminiscent of how an idler arm with worn bushings would sound like as it clunks and makes a heavy (solid) jiggling sound when driving over expansion joints and sharp irregularities in the pavement surface.

This is especially noticeable while creeping along at slow speeds and I notice that it often times occurs at the R/F wheel area, but also at the L/F as well.

I've had it up on ramps, and on a lift, and can find no looseness in the tie rods, drag link, or any other part of the suspension. I'm at a complete loss as to what could be making this sound.

It makes no difference if I have the brakes applied or not. And it doesn't matter if I am turning or not, the noise persists...only when going over expansion joints and the like.

The only thing that's been done to the front suspension is the addition of a Z06 sway bar (yes it's nice and tight) and lowered on the bolts down to the last thread. And the factory shocks appear to be tight as well, as is the steering gear itself.

It seems to me that this started shortly I had the front rotors resurfaced due to excessing pulsation...but that could just all be my imagination. However, I can make the caliper rock back and forth on the rotor a little by hand, (I thought that was a little unusual), but none of the attaching hardware was loose.

Anyone have any ideas what I should look for? It may not even be in the suspension at all, but that's what it sounds like to me.

 

[c4c5specialist]

HI there,
I would be looking at sway bar end links.
Just a theory.
Allthebest, c4c5

 

[MagikDraggin]

HI there,
I would be looking at sway bar end links.
Just a theory.
Allthebest, c4c5

I'd give your "theories" more credibility that a lot of some other's educated guesses. Thanks for the tip.....I know they were torqued down correctly when I installed them...but if the dealership had to loosen them in order to remove the rotors, maybe they didn't tighten them back up properly.

I'll check it out tomorrow and let you know. Thanks again.

 

[MagikDraggin]

Sorry, that wasn't it. All end links were nice and tight. I did find where the headers were knocking against a mounting plate on the rear of the oil pan.

I was told not to bolt the headers to it, as that would (or could) cause the headers to crack. At least the person who installed them could've taken the bracket off. I removed it.....stopped some of the noises I was getting from going over little bumps on rough roads.

But the one in the R/F wheel area still persists.

Is the caliper assy supposed to be able to "move around" on the rotor? I can actually rock this assy back and forth by hand, yet all the mounting hardware is torqued down tight. Is that normal?

To tell the honest truth, I don't see what's holding the thing on in the first place.

 

[wishuwerehere82]

Look at the nut on the ball joint on your lower right control arm.
It has to be loosened and dropped down to get a torx bit onto the brake caliper bolts. Maybe they didn't tighten it back up when they did the brakes.
EDIT**** OOps, I meant the wheel bearing bolts.****
What the heck, check it anyway.

And yeah, the caliper floats on spring hardware in the caliper mount. Not too much but you can slide it side-to-side fairly easily. But it shouldn't be floppy.
Maybe they didn't get all of the spring clips in. I would take the two bolts that hold the caliper mount on and pullit off to look at the hardware. There are 4 spring clips that the brak pads ride on in the caliper mount. The inner caliper is located onto two greased pins that allow it center as the brakes are applied.

 

[MagikDraggin]

Look at the nut on the ball joint on your lower right control arm.
It has to be loosened and dropped down to get a torx bit onto the brake caliper bolts. Maybe they didn't tighten it back up when they did the brakes.
EDIT**** OOps, I meant the wheel bearing bolts.****
What the heck, check it anyway.

And yeah, the caliper floats on spring hardware in the caliper mount. Not too much but you can slide it side-to-side fairly easily. But it shouldn't be floppy.
Maybe they didn't get all of the spring clips in. I would take the two bolts that hold the caliper mount on and pullit off to look at the hardware. There are 4 spring clips that the brak pads ride on in the caliper mount. The inner caliper is located onto two greased pins that allow it center as the brakes are applied.

That's some good stuff to check. I'm getting the vette ready for an extended road trip to the San Diego area...hoping to leave by this Wednesday. Got everything else done that needs doing.....except cannot locate the source of that annoying noise.

It is definitely coming from the vicinity of the pass side front wheel, that much I have ascertained. The only time it "clunks" (more like a heavy "jiggling" sound), is when the suspension is given a slight jolt (like an expansion joint) and for the instant that it is "free-floating", that is, in that space of time where the suspension stops compressing and begins to rebound.

This condition is not something I can easily duplicate with the car setting stationary.

I'll check your suggestions out in the morning and hopefully will have "good news" to report.

 

[wishuwerehere82]

The calipers should slide in and out(along the same axis as the axle) but should not be rocking. I think it's a 5/8" wrench that takes the two bolts off that holds the caliper on. See what you find in there, and good luck!

 

[gmjunkie]

Check the eccentric bolts in the Lower control arm's while your there!!

 

[MagikDraggin]

Check the eccentric bolts in the Lower control arm's while your there!!

For "GM Junkie" and "Wishyouwerehere", While installing the Z06 shocks I bought, I checked all of what you guys suggested I look at and found nothing loose.

Steering gear is ok, tie-rod ends ok, A-frame (I guess it's still called an A-frame), bushings ok, ball joints ok, end-play in the wheel bearings ok, calipers ok.

And you're right about the "play" in the calipers. It is not actually the caliper itself that's moving, but the entire rotor assembly along with the caliper....(because the wheel isn't on to keep it still; call me dummie for not noticing that before).

I guess I'll just have to live with it (or until something falls off). By the way, the Z06 shocks definitely toned down the "float" I was getting with the std shocks, and along with the Z06 sway-bars I already had on, I love the way it corners now.

Too bad they didn't simply produce an A4 Z06 coupe......I coulda saved myself a few bucks, what with all this retro-grading stuff I've been doing.