Vibrations at high speed + acceleration

[johnovision27]

Lets start with the symptoms.
I started noticing vibrations at speeds upwards of 130kmh (80mph) a couple of weeks ago. It was a very gradual onset and the intensity varied with acceleration. WOT, car felt like it was in a paint shaker. Engine braking, nice and smooth, ZERO vibration.
Since it started, the vibrations have been starting at lower speeds, now down around 60-80kmh. The intensity still changes with throttle position.

I've been having a lot of trouble determining where the vibration is starting from because the whole car shakes. The wheels are all balanced, and there isn't any shimmy or shaking in the steering wheel. Thats the only thing in the car that stays still!

I took it to Mitsu, and they recommended a wheelhub change on the FP side. It wasn't that bad, but to eliminate all the possibilities, that has been swapped out for a new unit. No other parts were found to be loose or failing.

Some car info.
Balance shafts eliminator kit
2.3l (perhaps the extra torque messed something up?)
All 4 wheel bearings replaced in the past 4 months
no vibrations based on rpm, all with speed

I've also done my homework and looked to what others were saying. I've seen tierod ends, CV joints, ujoints, etc.

My thought is a ujoint perhaps, but I'm looking for others input here as well.

Cheers.

 

[spook302]

I had a bad vibration at accleration on my car that took me awhile to find. i had to put it on a lift and start removing parts to find the problem. my cv axle on the drivers side started to bind up. Not get loose like they normally do when they go bad. There was no clicking sounds coming from it at all. The vibration took out my intermediate shaft bearing as well when it started to vibrate. I luckily started with the bad side first. as soon as I pulled the cv out I knew it was toast. You could barely rotate it at an angle. I grabbed my mid shaft and wiggled it and that bearing was toast. I had a good used shaft and bearing. Installed a new cv and its all good now. I had been searching for this problem for a month. Just looking at everything while under the car it all looked fine.

 

[agentorange313]

are all your tires balanced?

Right now I am getting a stupid amount of vibration, I know its from my driveshaft.

 

[AWD Devious]

are all your tires balanced?

Right now I am getting a stupid amount of vibration, I know its from my driveshaft.

I guess you didn't read this guys post. His tires are balanced.

 

[agentorange313]

sorry I saw the word wheels, not tires, I was skimming.


come to think of it, it might be your drive shaft.

I am thinking that since there are vibrations at higher speeds then there might be a correlation to your drive shaft, which increase in rotation with increasing speed. The out of the transmission in ratios, so in fifth gear, overdrive condition, the drive shaft is spinning faster then the engine rpm output.

Does anyone else think this could be the culprit?

 

[Quicksilver1695]

Balance shaft? I don't believe it would be as intense as you're saying, but it's a thought.

 

[BigBeans]

I can basically promise you it's a U-joint.

Get under the car and get a firm grip on the driveshaft on either side of each U-Joint and twist/shake. If you get any play, even a small amount, the U-joint is done.

 

[thomcasey]

Either a u-joint or a carrier bearing. A bad u-joint, if ignored too long, will eventually whear out a carrier bearing.

 

[johnovision27]

Ah yes. Love the quick replies you get on this forum!

I was thinking ujoint as well. I'll try and get the car up in the next day or 2 and take a look. Fingers crossed because thats the least expensive fix
Thanks for all the input.

 

[T-mun]

also check your front drive shafts for sign of wear on the flexible joint, happened to me once (my car is FWD).

 

[johnovision27]

will do.

Side note, any thoughts on driving an GSX with the driveshaft not installed? Might take me a couple days to complete this rebuild while still having to drive to and from school.

 

[BigBeans]

Side note, any thoughts on driving an GSX with the driveshaft not installed?

You can't do it because of the viscous coupler in the AWD system, it will tear stuff up.

A ujoint (assuming that's what it is) shouldn't take more than a couple hours, even the first time you do it.

 

[johnovision27]

Noted. Thanks.

What if you were to remove the diff aswell??

 

[Alan11]

Noted. Thanks.

What if you were to remove the diff aswell??

it will still not run...
don't drive it please...

 

[johnovision27]

Update:
I was able to reach the front and rear ujoints and both of those are rock solid. So only one left that could be messing about is the center one.

The rear cv axles seemed to have a bit of play where they meet the transfer case. this is vertical play, not lateral play. (up/down and forwards/back, not left and right)
Is this normal or did I potentially discover the culprit?

it will still not run...
don't drive it please...

ok, ok. just trying to explore some more options.

 

[DSMTyson]

what about the front cv axles?

 

[johnovision27]

rock solid as far as I could tell. No movement in any direction.

Now, if thats the case, then what would cause those joints to fail?

 

[DSMTyson]

I had a bad vibration at accleration on my car that took me awhile to find. i had to put it on a lift and start removing parts to find the problem. my cv axle on the drivers side started to bind up. Not get loose like they normally do when they go bad. There was no clicking sounds coming from it at all. The vibration took out my intermediate shaft bearing as well when it started to vibrate. I luckily started with the bad side first. as soon as I pulled the cv out I knew it was toast. You could barely rotate it at an angle. I grabbed my mid shaft and wiggled it and that bearing was toast. I had a good used shaft and bearing. Installed a new cv and its all good now. I had been searching for this problem for a month. Just looking at everything while under the car it all looked fine.

This.

I would take them off and make sure they are not doing that^^^ before you replace the rears. If they are fine, replace the rears unless you find something else in the drivetrain that could be causing vibration.

 

[johnovision27]

I just replaced the passenger side front hub, and that shaft was able to move freely when it wasn't bolted to the hub. I'll have to look into the driver side tomorrow and see what I can come up with. When I changed that hub a couple months ago, the axle boots were loaded with grease and sealed back up.

UPDATE:

So I got my buddy to ride along side/around my car and the conclusion is there is something seriously messed up with the driver side front axle.
He said it was wobbling back and forth. I just checked the brakes a couple days ago (after this vibration started) and the rotor as well as the wheel were installed correctly and torqued to spec.

I'll get it up on jacks shortly, poke around a little and hopefully come back with some answer.

 

[johnovision27]

UPDATE

Finally a nice sunny +4 here in Toronto and I had a couple of hours to kill.

Tore apart the driver side wheel well and looks like there was a grease shortage in the boot on the driver side axle, thus causing the top bearings inside to fail.
There is no sign of the pins or the snapring.

All other joints are solid with the exception of the rear control arm, the ball joint looks a little rough....

NOW, my question is, can i just replace that part or should I replace the whole axle?
I can get a new one from NAPA for $90 + core, haven't looked into OEM yet.

Cheers

 

[johnovision27]

Replaced the whole axle with a Napa one. 95-8378. MAKE SURE YOU MEASURE IT PRIOR TO GOING HOME AND TRYING TO MAKE IT FIT!!
The first one the gave me was the correct part number, but the wrong part and about 2" too long.
Resulted in me wasting the whole day wondering "what the *#$% did I put back wrong?!"

But all is good now and she is smooth as a..... you get the idea.

Cheers