When I reverse my car the back starts lifting up

Hi,

Looks like your vehicle is equipped with rear drum brakes. If this is the case, then more than likely you have the rear shoes are locked.

The way they work is the leading shoe or the one closest to the front of the car is used for braking while moving forward. The trailing shoe is for braking in reverse. They both apply force to the drum when you press the brakes but depending on the direction one is a primary and the other is a secondary shoe.

If the issue only happens in reverse, I suspect the trailing shoe on one or both of the rear wheels are locked up. So when you move forward the trailing shoe becomes the secondary shoe and the vehicle is able to move.

This will also cause the vehicle to lift up so it fits your issue. Let me know if you have questions but I would remove and inspect or replace the brakes as needed.