Water Pump - Usage

Number 84-6 (Gasoline)-25 Date 3/84
Subject: WATER PUMP USAGE - 1978-84 BONNEVILLE AND GRAND PRIX WITH 5.0L V-8 GASOLINE ENGINE OR 5.7L V-8 DIESEL ENGINE
Water pump package number 556283 available from WDDGM, now contains a pump with a sheet metal impellor. This pump is also being used on production engines.

Dealer Information Bulletin 81-I-202 defined criteria for the cast iron impellor. It must have square vanes and .045 inch clearance. It is no longer necessary to be concerned about this if a new pump with the sheet metal impellor is used.