http://www.courts.state.pa.us/OpPosting/Superior/out/A12004_05.pdf
There is no separate lender-borrower duty of good faith. Whatever such duty exists arises under contract law, etc.
A lender's decision to exercise its contractual rights is not a breach of the duty of good faith. A lender has no duty to give up its rights under contract or statute.
The opinion contains a good discussion of the general concept of good faith under sec. 205 of the Restatement (Second) of Contracts, and the UCC, 13 Pa. CS 1203
Donald Marritz, MidPenn Legal Services
