Now that I read over your posts. You say the entire car shakes. This could very well be your motor mounts or some problem with the car's timing. Possibly your spark plugs or distributor or something along those lines that make the car engine run smoothly... no hiccups. I would suggest a tuneup first...

 

Thanks guys.. I would think of tuneup because i did the following even then i am getting those hiccups..

1. Checked brakes from Pepboys. They cretified the it is brand new and no problem with it.
2. Rotated the tires to make sure that no lugnuts...
3. Changes oil.
4. Poured fuel line cleaner.

May be i try the tuneup next

 

Could be a bad wheel bearing as well, a cracked steering gearbox, or poor alignment. Best of luck to you, these can be a beotch to diagnose.

 

I would also say go with a tune-up. Even if it doesn't fix it, giving your car a tune-up is like giving a little kid a pixie stick...It makes it much happier, plus gives it a bit more pep. Changing out the spark plugs, wires, air and fuel filter doesn't cost a lot either.