A/C - Uneven Air Flow At Windshield Defroster Outlet
89chevy12GMC NUMBER: 89-T-30
GROUP: 1A-Heating and Ventilation
DATE: March, 1989
CORPORATE
NUMBER: 961101R
SUBJECT: UNEVEN AIR FLOW AT WINDSHIELD DEFROSTER OUTLET
MODELS: 1988-89 C/K TRUCKS
Figure 1:
Some 1988 and early production 1989 C/K trucks may experience a reduced air flow condition at the upper right side defroster outlet during the defrost operation. This condition is due to an insufficient amount of air flow directional vanes within the windshield defroster nozzle assembly. To address this condition, three (3) vanes have been added to the inside of the defroster nozzle assembly (P/N 15530575) to redirect the air flow (See Figure 1).
IMPORTANT: The addition of the three (3) directional vanes to the defroster nozzle assembly will correct the uneven air flow condition. It is normal for the defrost output air temperature to be cooler on the right side than the left.
Parts are currently available from GMSPO.
Beginning with the following VIN breakpoints, the redesigned defroster nozzle assembly was incorporated into production.
Ford Wayne GMC KZ514997
Pontiac East GMC KE517470
Oshawa GMC K1522243
For repair to vehicles under warranty, use the following Labor Operation and Time:
Labor Op: T7900
Labor Time: .8 Hr