Shimmy, not tire related

[J Wikoff]

How did the calipers contribute to the shimmy? I've replaced the driver front not too long ago, with no change. The passenger side is original though.

[MattStrike]

Maybe, if they are a little sticky, they are grabbing the rotor at the high spot.

[J Wikoff]

Wouldn't the warped rotor be more of a cause then?

[MattStrike]

Possibly, but a warped rotor should only do it during braking.

[J Wikoff]

I did the passenger side today. I couldn't get a good highway test drive, but it seemed lessened and it came and went. When I got home I found it leaking red fluid. I'm thinking I didn't get the CV fully seated.

[J Wikoff]

Ok, still got some shimmy.

It's got new tie rods, CVs, ball joints, endlinks, calipers, and wheel bearings. There is no pulsing in the brakes. It shows up around 40-50 mph, and starts fading away around 70. It kinda seems like it flares up a little when off the gas, coasting.

Ideas?

[SuperHbody]

Bring somewhere else and get a second opinion of the tire/bent rim. With it showing up at specific speed like that and lessening as you go faster, I'd say an out of balance tire or a bent rim.

[J Wikoff]

I need to take it for an alignment, so I'll get the wheels and tires checked out then.

In the meantime, I've ordered new 96+ L67 ignition coils to rule out a misfire. I have had MSD coils for a number of years, and I bought them used. I've read that lots of people have had longevity issues with them.

[J Wikoff]

I put on new coils and it made no change.

[Plemmons]

I wish I had seen this post sooner... If the shimmy seems to get a bit worse when you coast, I wouldn't think it to be the coils. As far as the front end work goes, I will never again replace just the balljoints on a stock bonneville, haha. You can get the control arms with bushings and balljoints and install them as an assembly, which is great. When I worked as a mechanic, we had a few customers come in with wheel shimmy issues and a couple times it turned out to be a tire manufacturing defect called "out of round." It just means that a tire is slightly elliptical and it will cause shimmy no matter how many times you try to balance the wheel. It's worth a check!

[2000Silverbullet]

I had a similar problem on another vehicle. It went away when I replaced the shocks.

[CatmanFS]

Might just need some new caliper bushings, you know, those little rubber things inside the caliper bolt holes. Maybe one is out of whack and it's sitting offset, causing it to rattle at medium speeds, and the rotational inertia of the rotor straightens it out.

My car did exactly what you're describing, but after getting ceramic pads in the front, and replacing all sway bar bushing it seems to have gone away, then again, maybe I'm just not noticing it.

After replacing all the sway bar links and bushing front and back the problem seemed to go away, then again if I start to shimmy at 50, I speed up to 75 anyway just to beat the soccer moms so yeah, all those things could help, but not if the problem is in the hub, so take a good look at that thing, and the little spindle. Sometimes small impacts with road craps can knock stuff a little out of whack and it might not start making noises till a few thousand miles later. Sometimes just taking everything apart and putting it back together can give it a new fresh feeling, and helps you realize the difference while driving.

[J Wikoff]

At this point, the control arms and the struts are the only things that haven't been replaced since the shimmy started. The struts are Monroe Reflex, with about 40-50k on them. I'm hesitant to replace them because there aren't any replacements that I know of that are as stiff.

If I do get control arms, it would probably be this and the matching one for the other side. It looks like there is a bushing in one side. What other bushings would I want to get?

http://www.rockauto.com/catalog/moreinf ... cc=1247408

Moog has these bushings. Is one or both of them already in the new control arm?

http://www.rockauto.com/catalog/moreinf ... cc=1247408

[2000Silverbullet]

The struts are Monroe Reflex, with about 40-50k on them. I'm hesitant to replace them because there aren't any replacements that I know of that are as stiff.

How can you be sure they are not bad?
I had shocks go bad after less than 50K miles

[J Wikoff]

I'm not sure at all. But as far as shot gunning parts like I have been, they are last on the list because I like having them, and are irreplacable.

[2000Silverbullet]

Oh didn't know they weren't available any more.

[skregal]

I've replaced all that stuff trying to get my shimmy to go away
and still have no luck. Almost everything that spins, supports,
or steers my 95 is new, and it still shakes a little on the highway.

I gave up.

[2000Silverbullet]

Have you guys had your tires road force load balanced?
Defects and damage to modern tire belting can produce funny balance problems.

[Backhoe]

My Dad and I have both had this issue, his on a Bonnie, and mine on the LSS. It shows at up at about 50-55MPH, and fades at about 75-80MPH. He has since sold his car, but I plan on getting under the front end to refresh some components to try and rectify the problem, but this issue seems to be a common problem judging by the responses here.

[J Wikoff]

Time to dust this off. Since I've tried to rectify this apparent front end shimmy, I've replaced the tires, hubs, axles, complete tie rods, ball joints, sway bar bushings and end links, control arms and bushings, calipers, and the passenger side strut (as of Sunday). The driver side strut will be replaced soon. The shimmy persists. Pads and rotors are fairly recent, more recent than the shimmy. If it's not the driver side strut, what's left to replace?