Peterbilt 353 Back Up Light Bulb Size

The Peterbilt 353 back up light requires unique bulb sizes 1156 and P21W for proper installation. Available data covers the specific range from 1986 through 1988.

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
1988	1156
1988	1156 (With Halogen Capsule Headlamps)
1987	1156
1987	1156 (With 4 Rectangular Headlamps)
1986	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 1156 is the sole bulb size specified for the back up light across all listed model years of the Peterbilt 353.
The 1156 is an ANSI-standard bulb recognized in both the United States and Canada, operating at 12 volts with a 21-watt output.
As a single-filament bulb, the 1156 serves one dedicated electrical function, which aligns with its application in back up lighting rather than a combined stop/tail role.
The 1156 uses a BA15s bayonet base, a single-contact fitting where the "s" denotes a single pin, distinguishing it from the dual-contact BA15d base found on two-filament variants such as the 1157.
For the 1987 Peterbilt 353 equipped with 4 Rectangular Headlamps, the 1156 is the specified back up light bulb, indicating this fitment applies regardless of headlamp configuration in that year.
A separate 1987 entry lists the 1156 without a headlamp qualifier, reflecting that the same bulb size applies across headlamp variants for that model year.
The 1988 Peterbilt 353 with Halogen Capsule Headlamps also uses the 1156 for the back up light, confirming that the headlamp type does not alter the back up light specification.
Because the BA15s base accepts only single-contact bulbs, substituting a dual-contact 1157 or similar bayonet bulb is not a compatible interchange for this application.