Hello all,
I have a 2002 cavalier LS that is shaking between 30-50mph. I can't really say when it started because i just kind of ignored it but it has gotten increasingly worse and it is to the point i can't stand it anymore.

Tires on front are a year old and have been balanced, front end aligned. I have even swapped out wheels and tires which did not help. I have replaced CV axles both sides with Carquest brand axles. Car has new ball joints maybe like 3-4 months ago. New struts last summer. New pads and rotors last week. New inner and outer tie rod ends about 6 months ago. Discovered a few weeks back top engine mount was completely busted so i replaced it and all the others as well. Control arm bushings are in good shape and can not get any kind of play there. I can not find any kind of play in any suspension part and the hub bearings are solid and no humming or grinding from those even when i put a load on them.

Can not locate this shake. It's a shimmy type of shake back and forth in the front end. I jacked the car up on jackstands and put the car in gear and put my phone down there to record. Having the car in drive and accelerating did not reproduce the shake most likely because there was no torque on the front wheels i'm assuming. I tried again this time power braking and sure enough there came the shaking like crazy and only at like 30mph. From the video footage it appears the entire engine jerks with some sort of rotational interference. This is the shake i'm feeling. I thought maybe bad CV axles but i got them swapped under warranty which was really hard to do with two of them, lol! And the shake is still there anyways.

I thought well maybe i should get another alignment but if it's doing it on jackstands its not the alignment. More than likely not CV axles either since i swapped them. Only thing left would be hub bearings. But i can't get them to howl or groan. Also why is this only when accelerating when wheels on ground or power braking on jackstands?

Bought this car brand new in 2002. It was taken care of and not beat on. Never any issues with transmission, leaks, slipping, nothing! Would something with the transmission cause this kind of shaking? Fluid level good too. After 50-60mph on the highway it's smooth as could be. A friend mentioned to me maybe it's the back bearings but i can duplicate the shimmy with the front end on jackstands and sitting still. It's going to drive me nuts driving around like this. And sorry but i have to drive this thing as long as possible. Can not get another car right now and it runs good.

 

Maybe jack car up then grab the wheels and see if you can get any up/down or back/forth play in them. Maybe get a 2x4 or long pry bar and see if you can get any play around the engine, wheels, etc.