I am experiencing high speed vibrations but only when engine is accelerating, when no load on engine vibrations reduce significantly. I tried driving slow with D3 gear just to see if it was issue with engine but again vibrations were minimal. I know my car needs sway bar bushings, steering rack bushings and very bad front rotors. This problem was even worse before I got new axle yesterday. Can you guys help me solve this issue.

 

Steering racks, ball joints, bushings, or rotors can possibly cause this. Since you already know you need some of that stuff, take care of that first. That might just fix it.

The vibration being only on acceleration sounds like an inner driver - part of the axle. Did you only get one axle?

 

yes just one axle passenger side. other one i replaced about year ago. My front rotors are bad, the y have big grooves in my rotors. Also when i rolling in parking lot i can hear one of the brakes squealing.

 

Today i noticed onet thing. Car constantly vibrates at high speed but the vib gets amplified when i step on gas pedal and then i start getting vibrations on car floor and steering. Also sometimes it feels like that i can hear my cars front end vibrating i dont know if its sound of engine or tires.

 

Sounds like a bad motor mount could be causing this...

 

sure as heck doesn't sound like brake rotors to me

 

i got oem new front and right side motor mount this summer and rear oem last summer. Today i was rotating my tires and i decided to check the old drive shaft i have. I can move the shaft sideways little bit and can hear it too with hand. Joints are in place just the center metal shaft.