Chevrolet G-Van Back Up Light Bulb Size

The Chevrolet G-Van back up light uses a 1156 bulb size for replacement applications. The chart contains bulb size specifications covering 1975 to 1995 vehicle production years.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
1975-1995	1156

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156

Other Locations

Additional Notes

The Chevrolet G-Van uses the 1156 bulb size for the back up light across all listed model years from 1975 to 1995.
The 1156 is an ANSI-standardized bulb type, meaning its physical and electrical specifications are governed by a recognized industry standard used across the United States and Canada.
The 1156 operates on a 12-volt electrical system, which is consistent with standard automotive DC voltage.
The bulb carries a 21-watt rating, which is a typical output level for single-filament incandescent automotive bulbs used in backup lighting applications.
The 1156 is a single-filament bulb, meaning it serves one lighting function only, as opposed to dual-filament types that handle two functions such as braking and running lights simultaneously.
The 1156 uses a BA15s bayonet base, where "BA15s" denotes a single-contact bayonet fitting with a 15mm base width. The single-contact design corresponds directly to the single-filament construction of the bulb.
The BA15s base is not interchangeable with the BA15d base. The BA15d is a dual-contact variant used on dual-filament bulbs such as the 1157, and substituting one for the other is not physically compatible.