Tires or something else?

My daughter’s 03 Hyundai Elantra just got new tires and for a while rode well. Now, there is a “bounce” @ 65mph and upon braking. I need to know which direction to take to investigate the problem…Thank you.

The “bounce” upon braking is something else - probably warped brake rotors. Fix that, then report back if the “bounce” at 65 mph hasn’t gone away.

Thank you. Will check on the rotors.

And the tire installers could have warped the rotors if they torqued the lug nuts improperly.