Hi my name is John.
Have you check the shock to see if it still hook up?
what year is your kia?
thats what i asked him he said it is the shocks but it feels like shocks to me
If it bounce up and down on this vehicle it has to be the shock,because that what hold it from bouncing.there know leaf springs on this Kia.
What did they say was wrong ?
Can you look under the car and look at the shock to see if there leaking or disconnected?
can you bounce the rerar of the car and hear it making the noise,if you can you can have some one do this and you lay on your back on the ground you can carefully place your hand on the shock and see if you feel it when it is being bounce by someone else.