Oldsmobile 98 Back Up Light Bulb Size

The Oldsmobile 98 back up light utilizes 1156, 1073, 2057, and P21W bulb sizes for various lighting applications across the vehicle exterior. Available data covers the range of 1953 through 1996 for the specified automotive lighting components.

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
1993-1996	1156
1991-1992	2057
1964-1990	1156
1961-1963	1073
1958-1960	1156
1953-1957	1073

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Brighter variant of 1157. 12V, 26.9W/8W.	2057
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 13W.	1073

Other Locations

Additional Notes

The back up light bulb specifications for the Oldsmobile 98 span model years 1953 through 1996, covering three distinct bulb types across that range.
The 1156 bulb is the most widely used type across these specifications, appearing in the majority of model years from 1958 through 1996, with only a few exceptions.
The 1156 is a single-filament bulb with a BA15s bayonet base, rated at 12V and 21W, and conforms to ANSI standards applicable in both the US and Canada.
The 1073 bulb shares the same BA15s bayonet base as the 1156 but operates at a lower wattage of 13W, making it a lower-output variant of the same base type.
Because the 1073 and 1156 share the same BA15s bayonet base, physical fitment between the two is possible, but their differing wattage ratings means they are not electrically equivalent and should not be treated as interchangeable replacements.
The 1073 bulb is specified for the Oldsmobile 98 in model years 1953-1957, 1961-1963, making it the designated type for those earlier production periods.
The 2057 bulb is specified exclusively for the 1991-1992 model years, representing a departure from the single-filament types used across the rest of the range.
Unlike the 1156 and 1073, the 2057 is a dual-filament bulb with a BAY15d bayonet base, rated at 12V with filaments drawing 26.9W and 8W respectively.
The BAY15d base of the 2057 is physically distinct from the BA15s base used by both the 1156 and 1073, meaning bulbs from those two groups are not interchangeable with the 2057 on a fitment basis.
The 1990 model year uses the 1156, while the immediately following 1991-1992 model years use the 2057, after which the 1993-1996 model years return to the 1156 specification.