This is from the recommended books thread for radiology residents and I basically agree. If you are at a program with low pass rates on the Core exam, try to be more aggressive with reading early on and consider personalized instruction.
Medical school/internship: read Learning Radiology: Recognizing the Basics
Week before rotation: read Core Radiology section relevant to upcoming rotation
During rotation (1st time): read basic book, such as Fundamentals of Body CT, Fundamentals of Skeletal Radiology, Fundamentals of Pediatric Imaging, Essentials of Nuclear Medicine Imaging, and selected books from The Requisites (e.g., Ultrasound)
During rotation (2nd time): read relevant Case Reviews +/- RadCases books
During rotation (3rd time or mini-fellowship): read more detailed book such as Stoller
During rotation (when encountering interesting or complex case): STATdx
During the year at random times (e.g., while eating breakfast, during commute, etc.): Aunt Minnie's Atlas and Imaging-Specific Diagnosis, Radiology Recall
Review for boards: read Crack the Core Exam, reread Core Radiology
Books not particularly helpful: Brandt and Helms