I need some help diagnosising a front end shimmy.

[KaptKaos]

My car is a fairly stock '73 1.7. Two years ago, I upgraded to turbo tie rods with bump steer spacers. A few weeks ago, I added a Tarret front sway bar and new rear springs.

Recently, I have noticed a slight shimmy in steering wheel. It varies with speed. It slowly seems to be getting worse. Yesterday, I rotated my tires front to back, to see if it was a wheel balance issue. The shimmy persists.

I have gotten advice that I should replace my bearings in the front. I do not know when they were replaced (if ever), so I am considering that as well.

I am looking for a set of procedures that will help me to isolate the problem(s). Ideally, a step-by-step process of things to check that will either identify or eliminate a component as the source of the problem. I don't want to just start replacing things until I find the problem, but I realize that sometimes, cheap replacements are just smart to do anyway (the aforementions bearings).

Thanks in advance for your help with this.

[Tobra]

In my experience with my Super Beetle, a McPherson strut vehicle given to "shimmys", my most successful effort to solve it was when I replaced everything at once, tie rod ends, ball joints, struts, bushings. IMHO, when I just replaced the ball joints, it came back sooner because of worn struts.

If you have a shimmy at 50 mph, but it is fine at other speeds, it is very possible you won't be able to just jiggle stuff and figure out what is wrong. A lot of the stuff in the front suspension is what I would term a "wear item" anyway. After a couple of decades or a couple of hundred thousand miles, stuff will just wear out and have to be replaced.

In your case, if you developed the problem after adding the stiffer tie rods, perhaps you just made a problem with the ball joints or somehwere else more evident.

[Acox914]

i mentioned check, tie rods, bearing PLAY, ball joints and bushings...

[Toast]

Oh yea? Well I said to get the tires balanced.

[cruiksdr]

I am having a similer problem as KaptKaos, and rather than start a new thread, I thought I'd bump this one to try and sqeeze some more thoughts out of people.

I recently rebuilt the front end on mine. I have new ball joints, new turbo tie rods, and new bushings. The wheel bearings have less than 3k on them. Earlier this year, I put flares on the car and 3" wheel spacers (Cookie Cutter Wheels). I have not gotten it re-aligned since putting on the spacers (I didn't think they would affect that).

At around 50mph, I start to get a shimmey that can get pretty pronounced. It doesn't really do it under hard acceleration and it doesn't seem as bad at higher speeds (70+). It does seem wors when I let the car slow down from higher speeds toward 50 to 60. The car also pulls to the right.

I thought maybe the wheel ballance was off, so I had all four redone. No effect.

Thinking that maybe the front end was falling off, I got under the car and torqued everything down. Nothing was loose. No help here either.

Could the alignment be off? I had the car aligned last year after I put the tie rods and ball joints in.

Any thoughts are appreciated greatly.

Thanks!

[KaptKaos]

In my case, I had three tires that had "bubbles" in them. The tread was separating from the body of the tire. The bubbles made the tires out of round, which caused the shimmy. Damn tire guy sold me tires that were 5 years old by the time I bought them.

Anyway, tires replaced and all is good now.

In the process, I also repacked my bearings and checked my tie-rods. My tie-rods were newish turbo tie-rods. So those were not at issue.

Good luck with yours! Post on the 914club.com board too. Lots of help to be had there as well.

[Tobra]

Pulling indicates likely alignment problem. When you say 3 inch, you mean 3 inch thick, yes?

Seems like changing the track 6 inches would do some funky things to your geometry to me, but I know nothing, or not much

[cruiksdr]

These suggestions definately help. I had not considered the tires.

Yes, the spacers are 3" think at the rear and 2.5" front. I did not have any problems with drivability for some time following the spacers. The tires are just 1 year old Toyos. They were run last year at a DE event with about 4 hours total track time. This year has been all street driving. How can I tell if I have tread separation? I have hit more than one serious pot hole (thy're unavoidable around here). Could that have casued this kind of tire problem?

Thanks!

[Jbagel2]

have you checked your tranny or engine mounts???

[cruiksdr]

Originally posted by Jbagel2
have you checked your tranny or engine mounts???

Yes, they're new (last year), but I have not re-checked to ensure they're torged down. This problem, however, is definately coming from up front.

Thanks!