A/C - Insufficient Heat
87chevy28Number: 88-121-1A
Section: 1A
Date: Jan., 1988
Subject: INSUFFICIENT HEAT
Model and Year: 1985-1988 M VANS
TO: ALL CHEVROLET DEALERS
A new heater core to improve heater performance has been developed for 1985-1988 M Vans. The new heater core, P/N 52451085, has more fins per inch and will increase outlet temperatures up to four degrees Fahrenheit.
The new core will fit into existing heater assemblies without any modifications. To install the new core, follow the instructions for heater core replacement found in section 1A of M Van Service Manuals.
The new heater cores were incorporated into production beginning with the following VIN breakpoints:
CHEVROLET - JB143302
Labor Op: D2820
Time: 1.3 Hours