[SaabScott]

0 to 70 km/h and everything is fine.
Accelerate as slowly or as hard as I want, stand on the brakes, take hard turns, you name it, everything is great!

However, when I get over 70, I get a slight shimmy.
Now, I think I know the cause of the shimmy - I had a screw in the front passenger side tire a while ago and don't think the balance is 100%.

That's not my problem ...
When I am over 70 km/h, I can feel something loose in the front end.
Strangely enough, things get worse when I try to accelerate above 90km/h.
If I hold steady at any speed, the feeling of something being loose diminishes, but not completely.
When I put my foot on the gas again, the feeling comes back again.

Braking is not an issue though ... rock steady at any speed.
High speed lane changes are not an issue either ...

Any thoughts as to what could be wrong?

 

[SPATL]

Could be a myriad of things.

Obviously lots to check.
Ball joints solid?
Wheel bearings.
Control arm bushings
etc...

Potentially just a high speed vibration on an old car exacerbates the slow demise of suspensions parts getting weak.

Any chance you can find a tire place with one of these?

The Hunter Ground force Wheel Balancer has diagnosed many problems that other wheel balencers have missed. It uses a big drum that presses against the tires while being balanced to simulate ground force. Might be worth a try to locate one in your area.

 

[PMI]

I would look for something susceptible to both vibration from the wheel out of balance at high speed and torque from acceleration. Something going out in the suspension (balljoint, bushing, front arb link, possibly engine mounts). In any case, I would get the wheel in balance or rotated to the back, then see if the problem is still there.

 

[SaabScott]

I'm going to put it up on ramps this afternoon and try to move everything and see if I can find something loose.
I will also take it into the local specialist (he needs to check something else too) to see if he can tell me what is wrong (I can most likely fix it if I can figure out what it is).

I'm not so worried about the tire at this point .. the shimmy is not bad at all ... and it is possible that whatever is loose is the cause.
If I wasn't feeling something loose through the floor of the car, I would start with the tire ...

 

[jrbrangi]

on a side note, the orginal Riddler from the Batman TV show died today

 

[SaabScott]

on a side note, the orginal Riddler from the Batman TV show died today

What?

Wow .... do I feel bad!

 

[earthworm]

Bushings, rubber or rubber bushings, no matter, the rubber, over the years becomes hard and then cracks. And often, a man cannot see this hardening nor the cracks and separation, until it is really bad..

Another culprit is the tires - more unseen stuff..

This is wonderful when young and pliant and able to absorb NHV with aplomb.

IMO, the on the car wheel balancer is better than off the car.....

Ever notice that with FWD, during acceleration, how the imbalance diminishes, and with power off how great the imbalance really is...

BTW, The worn out ball-joint had no effect on the shimmy from last year, this was due to a lack of good tire balance - having the weights in exactly the right place on the rim....

 

[SaabScott]

OK .. I haven't driven it yet, but I am going to go out on a limb and say that I have found the problem.

I got the car up on the ramps (don't try this at home kids - unless you have something in front of the ramps - I use little pieces of wood - otherwise you will scrape your bumper skirt up).
I grabbed my socket set and crawled under the car ...

Everything seemed tight.
Nothing moved that shouldn't.

So, I thought I would check the ends from the steering.
They were fine to.
So I went looking for the clamp on the steering rack (I've been meaning to add the little piece of silicon hose a la ERP - but haven't found the time yet).
I found the clamp without issue ... but the top bolt was almost out!

So, I've tightened that up snuggly and made sure the bottom one is good (it was tight).

Now I just have to take her for a drive and prove my theory!:cheesy:

 

[SaabScott]

I was wrong ... things are certainly better, but not fixed. :evil: