Intermittant vibration

Hi there
Since a while I'm getting a vibration....
when going on the highway, the vibration is NOT there initially. Then it gradually get stronger and stronger as distance goes on, but same speed.

Hitting the brakes make the pedal vibrate sometime, but fade out. then the vibration is gone for a bit, and come back slowly.

Note that this is at a constant 100km/h, not increasing speed.

I ruled out the wheel balancement due to the fact that it's not constant.

Everything seems to be tight, couln't feel any movement in anything.

Brake on the left side is way hotter than the right side, so I do suspect that the right side do not work correctly.

Sometime the wheel also kick on the left a bit while breaking.

I do not know if it's 2 problems or a single one.

At last wheel swap, the calipers seemed to slide correctly.

Also, I think I have air in the brake line, as the pedal is too smooshy for my taste, and I can't seems to be able to make the abs kick in (but good tires, so might be the reason?)

Note: top plates on the front suspension seems to have a bit of play, but I beleive it have no effect on this issue.

I'm currently lost, and I don't want to replace good parts...

BTW, the winter tires, on separate rims, also do the same thing.

It seems to get worse as time goes by.

I would have the wheels checked for balance, out of round, etc.

Are you feeling a pulsation, or ABS activation?

I.E., coming off the highway at 65 mph, and LIGHTLY apply the brake pedal, does the steering wheel shake? If yes, you have a pulsation....

pulsating brake pedal while braking. car shake.

2 sets of wheels and rims do the same thing.

steering do not seems to go left-right, if it does it's unnoticable, as the shaking of the whole car is covering it up.

As I said, speed up to 100km/h, no vibration at all. this show that the wheels are balanced correctly and all. Continue to drive and you will feel an increasing vibration. The faster you drive, the FASTER it come. once it's there, even going down to 50km/h you can still feel it.

Applying the brake make it fade away, even if you pick up the speed....

Yes, it's weird...

My current guess: badly working right caliper, that apply slightly, causing an hot spot on the disk, which cause local thermal dillatation, causing the pulsation when I brake. Braking even out the heat, causing the dillatation to be even... However that explanation is... too far stretched to seems right... If that is the case, it would mean a costly repair (disk, pads, caliper, rubber hose... on both side)... Expensive to try too...

You can drive the vehicle on the highway, with no vibration....then you hit 60-65 mph, and then the vibration begins due to an imbalance.....

. . . NO

I hit 100km/h, NO VIBRATION... THEN it start to appear slowly, WHILE MAINTAINING SPEED!

There is a good possibility that you have a bad CV joint. The increasing vibration may be due to wear in the joint and that is why it increases when you maintain speed. Most CV problems begin to show themselves at around 60 mph. I would have it checked by a mechanic.

CV Joint, I checked it. zero rotational play, slight "in-out" play from the transmission side but I'm pretty sure it's normal, after all it have to change length when the wheel go up and down...

What year ? How many miles on this GA ?

A CV joint can cause this as GTP Dad said, usually the early signs are excess vibrations. And may not even have much slop in them.

If the return clips on the top of the calipers are not retracting the pads fully you'll get some drag over time. Possible heat can make the drag worse.
Even bad roads do this, like highways too everyone is going the same direction and it causes the pavement to get little ripples in it. Thus causing vibrations.

Remember your tires air pressure also increases as they heat up the longer you drive.
I see issues like this and sometimes you never figure it out untill something breaks.

One other thing, is your lug nuts torqued to 100 ft lbs ??

grand am 2002 se1 l61, just bellow 90000km!

Wheels should be proprelly torqued, don't know how much as I use a gun (electric), but I manually checked the bolts, and seems tight enought.

But I'm seriously thinking it's a brake issue... front right is always WAY colder than left side, but no pull on any side while breaking, except some time, but I think it's the road condition at stop (the one before I park at home always pull, but the one before never? pull)

I'm suspecting some bad slide pins or something... but not sure if it's related to my problem...

sadly, I didn't got time to recheck again, and my back is killing me... but last time I checked, everything seemed fine (even the slide pins)

yes if the slide pins arent moving freely it can drag. I would make sure those are operational and that the clips on top the calipers are good and working.

And 1 other thing the pad with the wear indicator goes on the Inside of the rotor. This too can cause problems and is very common mistake.

And it is important to use a torque wrench to make sure your lugs are even to 100 FT Lbs. Its not about being tight enough its about being even all the way around.
If not, these are notorious for warping rotor(s), and its shake like a mofo when under heavy breaking!

And I guess if one of the calipers pistons are bad and not always allowing it to retract then this too will cause drag.

Hope that helps, keep us posted!

I watched a video today, that might send me on a track...
Basically I got trouble with the rear left wheel. I think I misadjusted it or something... need to be confirmed however.
The video was about a master cylinder replacemet, and the tech said that that car model use cross "wiring", so front right work with rear left. That would maybe send me on the track for the uneven front left/right brake heat. but that do not say anything about the vibration.

I doubt the rotor is warped because the vibration is intermittant. if it was warped it would be constant. Same with balancing.

I'm currently doubting a wheel bearing. I think my wheel is more noisy than what it used to be, and the noise is more pronounced when I turn. Can't say however if it's the tire noise, or wheel bearing. I couln't feel any slack last time I checked...

However, front right do some "clok" noise when I hit some bumps. I beleive it's the top plates for the suspension (they do make noise, grease help alot somehow)

As for drag... I do not notice a slowdown when I put the car in neutral, and I'm surprised by how long it actually take to slow down the car.... I would expect that if the brake was draging that the car wouln't go that far... I'm guestimating the 100-0km/g in neutral to be a few km of distance... I think 90-80 took about half a km...

Update: Today I did some small tests, but couln't do much as my wrist is in pain... BUT...

I did some tests:
Jacked front left:
- There is no feelable left-right or top-bottom play
- Direction slightly move, but seems to be all fine
- Wheel is hard to turn: seems to be brake drag
- While in drive (don't yell at me!) there is nothing to be felt.

Jacked front right:
- There is no feelable left-right or top-bottom play
- Direction seems to move easier, suspecting bad outside tie rod.
- Squicky sound when moving left-right.
- Wheel is easy to turn
- While in drive, at ~35km/h, there was a vibration.

While on the road:
- Turning left is ok.
- Turning right make noise.

Top plates on the coils also have some wear.

So, seems like I have several problems, not just a single one...


So to sum up:
- Seems like I might have a wheel bearing that is starting to go bad (right turn noise)
- Top plates need to be changed
- Possible extenal tie rod
- Dragging brake or bad wheel bearing or both
- Possibly another problem with the right wheel too?

Might cost me alot more than expected to fix all...

I think you are on the right track. If you have noise when you turn the wheel then the wheel bearing is probably going bad. It can also be the source of the vibration.

turning the wheel make no noise, but left-right make the squicky sound.

So definitivelly I have several problems, so I guess I'll have to start replacing parts and see when/if it fix it...

The top plates might be the squicky sound.

Next step, when I'll have time, will be to remove the wheel and redo the same test. if no vibration then I'll put a winter wheel.

I might have something on that wheel as I hit twice something on that wheel (one is a big stone on the highway... didn't got time to move... I'm surprised that the tire didn't blew up... a like 4-5" one... the car resonated!)

Finally an update on this issue.
After some death, move, winter, job loss and all...

Front right wheel:
- Loose link kit.
- Right outter tie rod worn out.
- Seized slide pin (wasn't or didn't noticed at last check).

Front left wheel:
- Damaged rotor (inner side)
- Outter brake pad 2/3 worn out, inner almost at the warning thing, also damaged (wasn't last time I checked)

Rear right:
- Trailing arm bushing shot, causing abnormal wear on tire
- Noticed some oil on the stut

Rear left:
- Some wear on the trailing arm
didn't removed the wheel, so do not know about the shock, but rest seems ok from an under the car view from jack.

Job done today:
Front right wheel:
- outter tie rod
- link kit
- full caliper (could have got the bracket only, but for 20$ more...)
- rotor
- brake pad
- bleeding

Job for tomorrow:
Front left wheel:
- link kit
- full caliper as a preventive mesure (yeah, could have kept it)
- rotor
- brake pad
- bleeding

Rear:
- Both trailing arms
- bleeding (preventive mesure, while also doing a partial oil change)

To do:
Paint touch (do not buy dupli color primer!)
Next year: 4 stuts...

It's funny how thing can degrade fast at time. A mechanics checked it last year and didn't noticed anything too beside the tie rod...

Another small update: front job done.

No more vibration, no more pulling, no more wheel kicking, almost all rattle gone (suspension top plates/mounts are worn out), brakes are colder and even temperature, no more "shot wheel bearing" noise.

So, most of the problem was the outter tie rod I think, with some being the brakes. The tie rod was probably just worn enought to cause some issues, but seized enought to appear fine when checked up... until recently.

Now, if I can have the trailing arm, I'll see if the feeling like the back slide in a curve will be gone...

Trailing arm done, car is "like new" :D