As you did not give the year of your Caravan I can only reduce this to three choices.
The piston in the rear caliper on the 2008 Grand Caravan is the "screw in" type. A special tool is required to do the job.
It is called a 10MM aleen head sockit
a brake caliper tool (really)
With a scan tool.
With a scan tool.
You need the Dodge fuel line release tool.
With a scan tool.With a scan tool.
YesYes
That requires a scan tool.
With an OBD2 scan tool.
Scan tool or battery disconnect.
A scan tool is required.