when im backing up..my car is making a wierd sound.

Hello, I appreciate you have a noise concern. But it's impossible to determine what the cause could be from where I sit because I can't hear your noise and I can't observe your vehicle. I would strongly recommend you have a local technician near you listen for your noise and evaluate the vehicle at the same time. That's a key to resolving your concern. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops