1996 Geo Tracker vibration when driving

[gorkyb]

So I recently did a whole bunch of work to the wheels on my Tracker, I had a shop strip the peeling chrome and powder coat them. They came out pretty good, at least a lot better than the peeling chrome looked.

During the wheels being refinished, I rebuilt the front calipers and cleaned and painted the rear brake drums, I also re adjusted the rear brakes.

After I put everything back together and installed the refinished wheels and tires (I had a shop mount the tires and balance them) the car is shaking when driving above 30 mph, to be more precise: the steering wheel has a left to right motion that wasn't there before. Then when I apply the brakes, it sometimes shakes a lot and sometimes it barely shakes, as I increased driving speed to around 60 mph the vibration on the steering wheel is hardly noticeable but if I go up to around 70 mph the vibration "sometimes" becomes very noticeable.

If I drive around 40 mph and apply the e-brake slowly, the car shakes a lot.

Since this, I have put brand new rotors and pads on the front, but the issue remains. Judging by the shaking when I apply the e-brake I am thinking I might have a warped drum in the back but I'm not sure. Before I go ahead and keep buying more parts for this car I was wondering if someone has any ideas about what I should check for and in what order. Sorry if the facts are scattered around on this post but I've been trying to diagnose this while driving and my thoughts about this issue are honestly very disorganized at this point.

Something else worth mentioning is that the car is lowered through cut springs which PO sold to me as "lowering springs" since I've had this issue I took a closer look at all 4 springs and there's evidence of them being cut, probably with a cutting wheel on a grinder. However keep in mind that the car wasn't driving like this before I did all the work with the wheels and brakes. I also had it on jack stands for about a week when the wheels were being redone, the front was jacked up from under the frame but I had the back sitting on the rear axle (not on the differential but on the sides, each jack stand a third of the way in) I am wondering if by doing this I could have bent the rear axle

[fixkick]

shaking steering wheel, brakes applied.
id say no , bent rear axle.
the brakes cause shaking, , usually this stops it.
maybe with torched springs as they are called, its got way off alignment? now?
if the brake pedal don't pulse back to your foot the rotor are true and so are the drums. (mostly) brake inspections look for cracks too.
my guess, is bad front end parts.
the ebrake trick? stumps me. wow.
id look for looseness in all 4 wheel suspension parts. id man handle the tires for, at 3 and 9pm the 12 and 6
then using a pry bar try to find problems at all 4 ends,
jackup body , not suspension, then as tire leaves ground put a crow bar under tire and reef up hard, see if there is looseness , and in wheel bearings. and up front funny action of the struts.

is you rear axle pig , top Y fork rotted away? as is so common? this will show up with Ebrake tests or violent throttle action.

spin all tires on car, see if one rim is bent?
swap tires around to find one that acts different?

that front wheel shaking is odd, i think its all up front this problem. I think the ebrake effect is due to its changing body bias. (tilt) and passing that angle to the front and inviting front end loosing control.

Keep in mind tire balance even when perfect will still find a loose front end part, that is because there is no such thing as a perfect balance. close but never perfect and that imperfection finds loose parts fast.
cheers.
some shops have on car tire balance and you can see parts fail as they spin up, amazing to watch too.

[gorkyb]

I bit the bullet and took it to Firestone. They put it on the "Road Force" balancer, it's 95% better, the guy that mounted my tires didn't so it right. I don't think I'll get it 100% until i put the suspension and tire size back to stock so I'll just leave it like this for now until these tires wear out.

[fixkick]

large tires on old cars, love to shake.
the large tire, is never perfectly balances. (unless, spun on car, way)
new shocks will help. (struts) and new tie rod ends of loose.
also the tie rod , dampener can be bad, or you need a bigger one for larger tires.
wheel bearing on the front must not be loose, the nut is set to 123-180 ft/lbs.
if not , it's will fail fast.
do not read any GM specs. they are dumb. GM hates ranges and reduces it to a single number , on this bearing that was dumb of GM.
the above is the true range spec'd by Suzuki and by the bearing maker.
one tightens the nut and lands on an alignment hole in the above range. and that act GM, is impossible with a single number.

Front end shakes.;
1: tire balance.
2: loose wheel bearings. (use the crush bearing specs)
3: loose tie rods
4: bad shocks.
5: bad tie rod dampener.
6: other suspension parts loose, (try to flex them with a stick or crow bar) look for excess movement. The Lower A arms have inboard mounts, are they loose?
7: the upper strut has mount and is infamous to be bad, in the rust belt.

good luck to you.

[fixkick]

big tires on old car, must be balanced super prefect. (on car balance machine, is one way to do that, not off car, only some shops have this)
or it will shake at speed.
good luck getting all that sorted.

https://www.youtube.com/watch?v=7UP97bO-MpU

[fixkick]

when done this way the guy, looks and sees that parts are loose
and tells you sorry this car can not be balanced until you fix, x,y,z parts. loose parts.