Chevrolet K5 Blazer front side marker bulbs utilize 168, 67, or 97 bulb sizes, while rear side marker bulbs use 168 or 194 bulb sizes. The replacement chart covers vehicle production years spanning 1975 to 1986.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Chevrolet K5 Blazer front side marker position uses four distinct bulb sizes across the 1975-1986 model years, reflecting changes in electrical specifications over that production span.
The 168 bulb is the most frequently specified size across both front and rear side marker positions in the K5 Blazer. It is an ANSI-standard miniature wedge bulb in the T10 form factor, rated at 12V and 4.9W.
The 194 bulb, specified for the rear side marker on the 1985-1986 K5 Blazer, shares the same T10 wedge form factor as the 168 but draws less power at 3.78W versus 4.9W. Despite this physical similarity, the two are not the same bulb and carry different ANSI designations.
The front side marker on the 1980-1986 K5 Blazer uses the 168 bulb, while the rear side marker for 1985-1986 uses the 194. Both are T10 wedge types, but substituting one for the other would result in a wattage mismatch.
The 1979 K5 Blazer front side marker uses the 67 bulb, which is a single-filament type with a BA15s bayonet base rated at 12V and 8W. This base type differs fundamentally from the wedge-style T10 socket used in surrounding model years, making the 1979 front position incompatible with those bulbs.
The 97 bulb, specified for the front side marker on the 1975-1978 K5 Blazer, also uses a BA15s bayonet base and is rated at 12V and 13W. It is described as a variant of the 1156 bulb family, drawing notably more wattage than the 67 bulb used in 1979.
The 67 bulb used in the 1979 front side marker position is described as a lower-wattage variant of the 1156 family. Although it shares the BA15s bayonet base with the 97 bulb used in 1975-1978, the two differ in wattage, with the 97 rated at 13W compared to the 67 at 8W.
The rear side marker on the 1975-1979 K5 Blazer uses the 168 T10 wedge bulb, the same type specified for the front side marker on the 1980-1986 models. However, these positions are on different vehicle generations and the shared bulb number does not imply cross-position interchangeability without confirming socket compatibility.
All bulb sizes listed across both side marker positions are ANSI-standard designations valid in both the United States and Canada, indicating standardized electrical and physical specifications under a common North American classification system.
The front side marker position on the K5 Blazer transitions from a BA15s bayonet base (used with the 97 and 67 bulbs in 1975-1979) to a T10 wedge base (used with the 168 bulb from 1980 onward), representing a socket-type change that makes bulbs from those two eras physically incompatible with each other.