01 Eldorado shimmy

[rockfangd]

HI all. Going nuts with my 01 eldo. I have been trying to work out all of the issues it has had.

There is a shimmy coming from what feels like the front et nd. I can really feel it at my feet.

It does it all the time at pretty much any speed. It varies by day it seems. Some days it is bad enough to make the steering wheel shake, other days it seems hardly noticeable.

I find if I brake moderately it feels worse but as I get down to lower speed it is better.

Here is what I have done

replaced tires

rotated tires

replaced 1 damaged rim (curb rash)

replaced brakes all the way around. Pads and rotors.

Rear knuckle bushings ( were shot)

Right front hub assembly. (no play but was loud)

torque struts(were shot)

checked front and rear end all seems good now but the shimmy wont go away

Took to alignment shop for alignment and rebalance. Tech found nothing obviously wrong, tires were balanced.

Called company about brakes and they told me to try bedding them again. Tried it tonight and same problem.

I am stumped again. Only thing I can think of is that one of the rotors may not be machined properly and still has a smooth braking surface. Other than the shimmy issue car is excellent.

Thanks all. I figured before I change anything else I would share my trouble

[KHE]

I would think that since it does it at speed, you could rule out any of the brake components unless there is a dragging caliper but then you'd notice the car pulling in one direction or another.

How are the tie rod ends and ball joints? I had a similar issue on my '05 Deville and one of the tie rod ends ("lubed for life" - no grease fitting) was bad at 60,000 miles. A new tie rod end cured the problem.

I'm not sure if GM was using the permanently lubed ball joints on the '01 Eldorados but even with a greasable tie rod end, someone needs to grease them. It's possible the previous owner never greased it and it wore out.

[barczy01]

Start with the basics. If you think its a tire or wheel swap it with the left rear. Road force is very important on Cadillacs 1998 and beyond for tires having less than 8lbs of road force per tire. Just balancing a tire won't pick up any tire runout issues.

What kind of tire is on the car?

If you can, jack up the LF wheel and put your hands at 9 oclock and 3 oclock position and shake the wheel back and forth. Any play at all?

Next, put hands at 6 and 12 oclock and shake up and down and check for play.

I assume the ball joint was loaded and checked by the mechanic.

[MAC]

Check the engine craddle to make sure bolts are tight and for rust/deterioration, particularly rear bolts and bushings.

[airmike]

What barczy01 said, road force balance is important. Thats the only way my shimmy went away. Don't rule out the other things, but a regular balancing did me no good.

[rockfangd]

The tires are kellys, They are excellent, I pulled them from my deville. rotating tires did no good.

I have found no play in front end, but I will recheck the balljoints.

I might add that I checked the forward (vertical control arm bushings) because I know they are common to tearing. Both look fine

When the tires were on my Deville I had no shimmy.

[rockfangd]

Ok so I think I figured it out. I checked it really good again tonight and the right outer tie rod is bad.

I told the guy at the alignment shop that I swore I felt some minor play in that side. Dont know how he missed it.

I am going to try to change both sides and see if he will take care of the realignment and will post back.

Balljoints are good

[KHE]

The alignment guy should do the alignment at no cost to you. Usually, the alignment guys are the first to point out bad suspension components.

[rockfangd]

Well. Tonight I replaced the tie rods. Right was bad, both were dry.

Car still shimmies just the same.

I will say it is tighter and more responsive.

Now let me ask this

MY 97 Seville does not shimmy at any speeds, so in theory if I put the tires from my seville on my eldo it shouldnt shimmy right?

I dont know exactly where I can get the tires road force balanced. Most shops only have regular balancers. I am afraid of what it will cost to get them road force balanced.

Front end is tight

Cradle looks and feels fine.

I am right to assume it must be the front because the wheel shakes?

I also checked the runout on the front rotors and it was no more than .002 on both sides. Which I assume is completely within spec.

Nothing is sticking with the brakes.

It goes back in for realignment monday so I will find out more

[KHE]

I don't think the Eldorado had the issues with needing the tires road force balanced like the 200+ Devilles and 1998+ Sevilles did as the Eldorado was the carryover chassis. You can go on Hunter's web site and search for a location that has the road force balancer.

When I needed tires for my 2005 Deville to replace the factory tires, I thought, "Here we go.... now I'm going to have to fight the balancing issue." . I bought a set of Michelin Harmony tires and I told the tire shop that they needed to road force balance them. They told me that they would balance them with the regular balancer and If there was an issue, they'd road force balance them at no charge. There was not an issue - the car rides as smooth as could be and that was two years ago so I must have been lucky.

[rockfangd]

well like I said when I had the tires on my Deville it rode perfect. No shimmy at all. On this cat it shimmies. Looks like exact same suspension setup as my 97 Seville. But like you said the eldo was the only one to carry over the same as the 96-97. Everything else changed

[KHE]

Have you checked the inner tie rods? They can go bad and exhibit the same symtoms as the tie rod ends.

Since you swapped known good tires and the problem is still there, it has to be something in the chassis - ball joints, tie rod ends, inner tie rods, loose rack & pinion bolts, etc.

[airmike]

As far as the balance goes, my local caddy dealer did mine for $35 in southeast Kansas.

[rockfangd]

for all 4?

[rockfangd]

Well had realignment done yesterday.

Wheel is perfect. Drives straight, still shimmies though. He said it may be one of the axles causing the problem. He could not find anything obvious

[rockfangd]

this shimmy issue is driving me nuts.

I really wish the alignment shop was able to figure it out.

All anyone ever tells me is (oh it rides nice, good to go)

Even though clearly it wasnt after the first alignment, maybe for someone else it would be but not me.

Tonight I just went over all 4 corners quick,

Set all 4 tires to 32 psi per the tag.

I have a gut feeling that I have some pulsation in the rear brakes(no surprise.) I will have to check warranty

I swear it varies. Sometimes it is bad enough to make the steering wheel shake back and forth moderately., but most of the time it just shakes a little bit.

I find it shakes the most between 10-30mph, but shakes at just about any speed.

It seems to be worse when slowing down.

I am thinking too hard on this one, I am thinking it may be a bad axle or engine mount.

[barczy01]

So, rotating the tires didn't change a thing? Cv axle leaking? Does the shimmy improve or change with temperature or driving time?

[rockfangd]

No obvious axle leakage, Left axle looks to have been replaced rather recently.

Seems to vary by temperature.

[KHE]

No obvious axle leakage, Left axle looks to have been replaced rather recently.

Seems to vary by temperature.

Left axle recently replaced? Maybe it is a POS aftermarket mart that is not balanced properly?

You might want to look for a shop that works on axles, driveshafts, etc. and take the axle to them to have it checked.

[JohnnyG]

Low speed shimmy is caused by one or more out of round tires. Due to suspension differences, you may not have felt it when the tires were on the other car. I had a 1981 Toyota Cressida (best car ever made) that did the same thing. Changed tires from a set of Dunlop seconds, and all was fine. I suppose this kind of issue might also be caused by mounting the wrong size or series tire on an incorrect rim, thereby seating the bead unevenly.

$20.00 says that nobody, not even the guys balancing the tires, checked for roundness of the tread area. Sometimes steel belts can break or move inside the tread area causing this condition. Other times, as in my case, the tires were just poorly made.

Keep in mind that I'm not even talking about road force balance here. Even though it defies logic, road force balance may not detect this kind of physical radial runout since the "force" on the road may remain the same. When I had my Cressida, road force balancers weren't even invented yet. Nor have I run into an out of round tire since, so I have no basis for comparison.

If you feel this shimmy only in the steering wheel at this low speed, borrow a set of front tires (ONLY) from SOMEWHERE and try them out. If the shimmy varies, or seems to move around the car, all 4 tires are bad.

[rockfangd]

tonight I jacked up the front end.

I grabbed the cv axle at the transmission and at the wheel, Found some play at the transmission side joint. Both sides but more on the driver side.

I am not sure if there is an allowance of play in the axles where they ride in the joint, that could be the answer(or not to my shimmy)

What I mean by play is when you turn the tire back and forth while holding the innermost part of the axle it has play.

Anyone have any info on this.

Engine mounts seemed ok but I will check them another day.

[rockfangd]

I am trying to get ahold of someone who has a dyno. I am almost thinking it would be a good way to see something I am missing.

I am also going to try to get a senior tech to look at it at my local tire warehouse. They deal in quite a bit.

I dont want to keep changing things around and not find the actual cause.

[MAC]

tonight I jacked up the front end.

I grabbed the cv axle at the transmission and at the wheel, Found some play at the transmission side joint. Both sides but more on the driver side.

I am not sure if there is an allowance of play in the axles where they ride in the joint, that could be the answer(or not to my shimmy)

What I mean by play is when you turn the tire back and forth while holding the innermost part of the axle it has play.

Anyone have any info on this.

Engine mounts seemed ok but I will check them another day.

I owned a '94 Eldorado and can tell you that there was some play in the front Drive Axles. The axles are made to be able to slide on 6 roller bearings within the transaxle based on road conditions. And when the car was jacked up there was also some back and forth play that was not necessarilly related to a U-joint being worn. The way to check for a worn U-joint with these axles is to know the ovbious signs. Simply feeling play may give a false positive. I replaced one shaft due to a worn U-joint. It was somewhat tedious because I removed the Control Arm bolt so I could pull the strut away to remove the shaft from the hub assembly. Since downward pressure is exerted on the strut assembly by the spring, it was a bit time consuming to re-align the Control Arm bolt holes.

[rockfangd]

well guys tonight was a good example of what I mean about the moisture making a difference.

It was raining a little bit on my way home tonight and it shook like heck.

I feel it mainly under my feet but also in the wheel and in my seat.

It all feels the same.

Almost feels like wheel hop, especially going around curves on the highway.

I felt like I was riding in a vibrator tonight.

I will have to call My local tire shop and get another opinion.

I cant imagine it is any good for the car. Especially if it is an axle problem.

I still think a dyno might show something, but dont know of anyone locally that has one

[Cadillac Jim]

Please pardon me if this has already come up, but are the CV joint boots all OK and sealed? This sure sounds like a bad CV joint to me.