1998 COMPLETE bulb list for exterior and most interior aside frome inside gauges

[Kejross]

1998 Pontiac Grand Prix Light Bulb Socket Sizes
Low Beam Head Light Bulb Size: 9007
High Beam Head Light Bulb Size: 9007
Parking Light Bulb Size: 3357A
Front Turn Signal Light Bulb Size: 3357A
Rear Turn Signal Light Bulb Size: 3057
Tail Light Bulb Size: 3057
Stop Light Bulb Size: 3057
High Mount Stop Light Bulb Size: 1141
Fog/Driving Light Bulb Size: 880
License Plate Light Bulb Size: 194
Back Up Light Bulb Size: 3156
Front Side Marker Light Bulb Size: 194
Rear Side Marker Light Bulb Size: 194
Ash Tray Light Bulb Size: 194
Glove Box Light Bulb Size: 194
Map Light Bulb Size: 168 or 212-2
Step/Courtesy Light Bulb Size: 168 or 194 or 74
Trunk/Cargo Area Light Bulb Size: 920
Under Hood Light Bulb Size: 561
Instrument-General Light Bulb Size: 194 or 37 or PC195 or PC74
Hi-Beam Indicator Light Bulb Size: PC195
Automatic Transmission Indicator Light Bulb Size: 194 or 37
Directional Signal Indicator Light Bulb Size: PC74


taken from: 1998 Pontiac Grand Prix Light Bulb Socket Sizes


you can click that link and other years/models are on the far right