Summary of information from manufacturer:gmreviewed the matter and...has not identified a safety-related brake condition that requiresfield correction.analysis:it appears that the parking brake actuation system or thepistons within the caliper can seize prohibiting rear disc brake func-tion.a seized calipers can result in uneven brake operation (pull)and/or total loss of the emergency brake function.status:test request at etf and near completion.awaiting GM response to June 17, 1988 information request.===
