[Tylinol]

Hi everyone. I have what may or may not be an actual problem. I've noticed on the freeway (and really any speeds above 40 or so) that my Milano kind of rolls its body to the left and right as I'm driving down the road, sometimes requiring a tiny bit of steering input to keep straight, when it then pitches in the other direction.

Is this a natural thing? I've heard that our suspension setup allows for quite a bit of body roll, but could I have something worn out that I need to fix? I replaced the front anti-sway bar bushings a couple months ago, but I have had the swaying issue since I got the car.

 

[Gubi]

No, that's absolutely not normal. Worn bushings somewhere, I'd think. First place I'd check is the Watt's linkage at the rear. Or maybe a blown shock or two? How do the corners feel if you bounce it?

Could also be your alignment is way out of whack.

 

[Tylinol]

The corners are very stiff; I can hardly get any movement at all which seems like how it should be in a sports sedan like this. Alignment and balancing was done at a European car specialist when I got new tires last year (about 1500 miles ago), so I think it's good too.

My front anti-sway bar bushings were badly worn last year, which is what I originally thought might be responsible for the swaying, but replacing them didn't seem to make any difference.

 

[Gubi]

Okay, check the Watts linkage bushings then. Also the bushings on the caster arms where they meet the body in front of the front wheels. Both of those commonly go bad and cause all sorts of weird steering issues.

Neither is a very difficult job to replace.

 

[Del]

I would check the front end alignment to make sure you don't have toe out, as that can cause the car to tramline (track or steer) to either side of the ruts worn in the pavement caused by heavy trucks. Extra wide tires will also have this behavior. Really worn freeway lanes can be a headache to keep the car going straight, wanting to "wobble" so to speak to one side of the lane or the other.

I might also check the front suspension sway bar lollipop bushings. These can wear out, or even fall out, causing the car to have slop in it's roll stiffness.

 

[Alfar7]

wobble

Shocks are not equal in bump/rebound.........

 

[Del]

In steady state driving on smooth but truck rutted freeway roads, the shocks are probably not a significant factor in this problem, as they would have little movement. On bumpy roads, oh yes.

With the 164s, the original alignment specs called for what was a great deal of toe out in front. Among other problems such as a very increased tire wear rate, this toe out caused the car to be inordinately sensitive to this tendency to climb the sides of the truck caused ruts in the pavement, worse with wider tires.

Reducing the 164 toe to zero in order to improve front tire wear significantly reduced this tendency. I would imagine that the normal toe in alignment of the Milano should further reduce this tendency. Our Milano with that alignment sure isn't sensitive to it.

Our Milano has the stiffer aftermarket stabilizer bars and springs, so it's roll stiffness is greater than the average Milano, which didn't have nearly that level of roll stiffness, rolling a fair bit in turns. The excessive(?) rolling effect would be amplified by the rut climbing tendency. That's why I suggested checking the stab bar lollipop bushings for excessive wear/softness.

 

[Tylinol]

I've been paying special attention to it on the road for the last few days, and it feels like it is coming from the rear of the car, as if the rear suspension is swaying and taking the rest of the car with it. A quick look at the Watts linkage bushings shows that they don't look so great; I think it's time for me to re-bush everything in the suspension that doesn't require major disassembly.

 

[Del]

Had to replace the bushings back there in our Milano at 100k miles, but the car never did exhibit the behavior you have described. We run 205/55-15 Michelin Pilot Exalto tires on the car.

 

[Gubi]

The Watt's linkage bushings are very important in that the linkage locates the rear axle left to right. If there's any play in the bushings it'll come out as the rear axle trying to steer the car, which sounds like it's what's happening.

Fortunately they're pretty easy to replace.

 

[sidewaysalfa]

Watts link bushings

Sounds like my Milano problem. It was sort of like driving a boat as the car shifted right and left, from the rear end.
One bushing was almost non existent
I had a good Watts bar with bushings from an old Alfetta GT and that solved the problem.