2002 Other Suzuki Models Vechile instability

Hi,
Iam facing terrible trouble with my car, at speeds between 20 and 40kmph the front passenger side tends to jump, this dissapears at high speeds.
I have got all four tyre balanced, replaced front two tyres, alignment has been done, shockabsorber has been checked.
I cant understand what the problem is!
Could you please help me as to what is the reason for vechile jumping at such low speeds and what all parts I need to check?

Thanks.