Any ideas on what would cause a random high speed vibration? When the vibration starts it starts as a low vibration, usually above 55mph, & as you continue to drive it gets much more severe but not necessarily associate with speed once it starts. The steering wheel shakes back & forth & you feel the entire vehicle vibrating. When applying the brakes, there is major pulsation in the brake pedal but no pulsation in brake pedal when the vehicle isn’t vibrating. The only thing you can do once the vibration starts is come to a complete stop, then sometimes it goes away. The tricky part is that I have driven for an 1-1/2 hours before without it happening, so it is really challenging to figure out what is happening.

Things I have already tried & replaced.

1. Replaced front wheel bearings
2. Replaced lower control arms with new ball joints & bushings
3. Removed rear driveshaft assembly as well as replaced it (vibrations happened with no shaft in & with a new shaft)
4. Balanced all 4 tires
5. Replaced 2 very worn tires, so now all tires are with in 20% of new
6. Replaced rack & pinion & had the vehicle aligned (not because of the vibration but it did it before & after)
7. Replaced the rear brakes (pads & rotor)

All suspension component visually look good & as the car drives down the road you cannot see any tire bounce in any of the tires.

Any suggestions would be appreciated.

 

It'is a little far out, but did you consider putting the front wheels on the rear and the rear on the front and see if any difference?

 

Sorry, I forgot to put that as well. Before replacing 2 tires I rotated all four... still the intermittent vibration continues.

 

Your vehicle has all wheel drive, and you still had the problem with the rear driveshaft off, what about the front driveshaft ? Condition of motor mounts?
Because you state the steering wheel shakes ,that points to a steering system/linkage problem. Is the power steering system losing pressure at times or sending false pressures to the rack? You didn't mention checking that part out.

 

The front are cv axles & I haven’t seen any damage. They don’t look bent either. As for the rack & steering components, they are all tight & new. The vibration happened before having those replaced as well.

 

Any Solution gbudd?

 

Unfortunately no. I took it to 3 different transmission specialists & they had no luck either. It seemed that a cause could have been brake related so I completely disabled the ABS because it seemed that all 4 brakes would start to apply on the own, or they weren’t releasing after applying. I replaced one sticky caliper as well as re-bled all brake lines. I was never able to find what was causing the random vibration.

 

I'm having the exact same problem with my 2011 Chevy Equinox LTZ. I've taken it to 3 different auto shops and it's still doing the same thing. It's driving me crazy. Did it ever stop or did you ever figure it out?

 

Unfortunately no, I finally threw in the towel after many many months, thousands of dollars & too many hours to keep track off trying to diagnose this issue. I had very seasoned transmission specialist that wouldn't believe me in how bad it was vibrating/shuttering... Until I videoed it happening from the drives seat, he still didn't believe it because he had driven it many times without issues, then I took him for a ride. He kept it for 3 weeks & did all kinds of diagnostic work because it was something he had never seen. He finally told me that this was beyond his expertise & suggested to move on from it. Which I did.

Sorry I could not be of more assistance, I feel your pain!

 

The exact same thing is happening with my 2014 Chevy equinox! Comes on sporadically, shaking in the front half and steering wheel, sometimes even a thudding noise from the center console, severe jerking while breaking. Sometimes it goes away while driving at higher speeds.

Took it to the Chevy dealership and my mechanic multiple times. My mechanic finally thought it was the break booster and replaced it… $1600 later for everything and it still does it!

At my wits end and looking to just get rid of it now. Insane problem.