Drums and shoes.
Drum.
There are a couple of things that can cause your Pontiac antilock brakes to lock up. The most common cause is a malfunctioning ABS sensor.
Pick up a Haynes or Chilton manual for your car. Follow their directions.
Canadian Tire charges $300 or so, you can do them yourself for $100
The only part that is needed to replace your 1997 Pontiac rear brakes is a break assembly kit. The brake assembly kit will have everything you need.
Take it to a mechanic. Easy, simple, costs a little more, but it gets done right.
Pick up a Haynes or Chilton manual for your car. Follow their directions.
I need help on fixing my back brakes on my 1997 sunfire
The best place I've found to get your brakes replaced is the local muffler man. Any type of smaller garage in your area will be able to take care of your brake problem at a fraction of the cost of taking it to the Pontiac dealership.
Should be big grey block with 4 prongs, in the fuse box under the hood
It may be your CV joints