CV Shaft?

[libbybapa]

Quite new to my '94 Sidekick JLX. It has a bit of odd steering wheel motion where in driving straight the steering wheel likes to shimmy back and forth. The effect comes and goes erratically. Although the speed of the shimmy motion is wheel speed dependent, whether or not the motion is present it is not. The motion corresponds very precisely to that of a worn out CV joint I've experienced before in FWD vehicles. A friend was saying that the Sidekick is normally rear-wheel-drive and only uses the front when placed in 4WD. So, my theory is that the auto-locking-hubs are not unlocking and that the CV shafts are worn causing the vibration. Reasonable? Other ideas?

Andrew

[jtgh]

this is RWD, and the CV on this car is almost never used (part time 4wd is what it is)

1: wheelbearing ever checked, ? 15k service point on the newer kicks. was 7.5k.
2: wheel balance.?
3: check for play in steering, wiggle it underneath, in fact a full front inspection is in order.
look, pry, feel, look for missing bolts , oops.

how may miles, mileage can tell a great story.

50k, 250k ? miles ?

no wheel is in pefect balance.
so if there is play , these imperfections are amplified.

id not drive a car with wheel shimmy.
until i looked.

[libbybapa]

I didn't think that wheel bearing or wheel balance would be intermittent. Most often the vibration is not present at all.

160,000 miles on it. I just got it a couple of days ago and have absolutely no service history on it.

Andrew

[jtgh]

your forget temperture.
as is warms up it gets looser.
speed , temperature and road surface. all effect it.

you have intermittant wheel shimmy. ok , most are. , but why?

do you have non stock wheels or tires?

the tire balance can and do what ever it wants to do.
ive seen tires do this at 55mph, not 54, no 56, the key is resonance.

every thing has a natural resonance.
all
when new, the front end is tuned way above any speed you can reach (unknown spec)
so the car is naturally , uneffected by bad tire balance. (all is not loose)
ask any tire expert, get way longer answer.
but
when the tire is unbalanced on an old car , the loose bearing or even a looses tie rod will allow the resonance to be lower. (just asking for shimmy)

out of balance forces , and loose , hate each other.

most folks not want to examine the front end , choose to just balance the tires.
sometimes this works, other times it just hides for a while , the loosness.
sooner or later, it comes back.

There are tire balance
and on car balance. try that ,as it will fail right in front of your eyes on the machine.
and the guy running the show will point and say, see that's no good.

that , there is too loose, feel it?

[libbybapa]

As I mentioned before, the shimmy is intermittent and doesn't correspond to any particular speed, road condition or amount of time that I have been driving. It is usually not there at all, but very occasionally and, as far as I can tell, randomly appears fairly pronounced. Tomorrow, if I have the time, I will jack it up and thoroughly inspect the front suspension, wheel and steering components and rotate the tires front to back.

Andrew

[jtgh]

cars wear , out little by bit, and suspension play and steering, will do that same.
at some point, it be comes marginal.
just a certain looseness, (temperature and run time effects this)
tire balance , over size wheels and tires on small cars are problematic (suspension tuning)
how stock is car?
you are wise, many folks just ignore problems and drive on.
anytime cars, make noise,it is good to check it out.
most of the time it important.
i was keying of this statement.

Although the speed of the shimmy motion is wheel speed dependent

[relicduke]

Even mud or snow inside a wheel can cause a shimmy,Jerry's right about the wheel balance,I find that most pronounced at about 55mph.
For ckecking ball joints,do you put the jack under the control arm like a rwd Chev?