The GMC K2500 Suburban side marker requires a 194 bulb size for proper installation and function. Data for the specified lighting component covers the period from 1995 through 1999.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The GMC K2500 Suburban uses two bulb types across its front and rear side marker positions: the 194 and the 168. Both are ANSI-standard miniature wedge bulbs sharing the T10 form factor and a 12V operating voltage.
Although the 194 and 168 share the same T10 wedge base, they are not electrically identical. The 194 draws 3.78W while the 168 draws 4.9W, meaning the two types differ in wattage despite their physical similarity.
The front side marker on the GMC K2500 Suburban used the 168 bulb from 1979-1986, then transitioned to the 194 bulb for model years 1992-1999.
The rear side marker position uses the 194 bulb across all listed model years, spanning 1979-1999.
For model years 1992-1999, the front and rear side marker positions on the K2500 Suburban both take the 194 bulb, making the same part applicable to both locations during that period.
For model years 1979-1986, the front side marker requires the higher-wattage 168 bulb, while the rear side marker requires the lower-wattage 194 bulb, meaning the two positions are not interchangeable during those years.
The 194 is the more widely used of the two bulb types across the K2500 Suburban's side marker specifications, appearing in both front and rear positions across the majority of listed model years.