GMC K25 Suburban Turn Signal Bulb Size

The GMC K25 Suburban front and rear turn signal bulb sizes include 198, 1156, and 199 configurations. The replacement chart covers vehicle production years spanning 1967 to 1978.

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

Front Turn Signal

If US Type and EU Type show the same value, a direct cross-reference for this bulb is not available or the data is insufficient.

YearsUS TypeEU TypeShop
1973-1978198198Check Price
19721156P21WCheck Price
1971199199Check Price
1968-19701156P21WCheck Price
196710341034Check Price

Rear Turn Signal

If US Type and EU Type show the same value, a direct cross-reference for this bulb is not available or the data is insufficient.

YearsUS TypeEU TypeShop
1973-1978198198Check Price
1972199199Check Price
1969-19711156P21WCheck Price
1967-196810341034Check Price

Bulb Specifications

Description Type Shop
ANSI standard (US & Canada). Miniature wedge bulb (T5). 12V, 2W.198Check Price
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.1156Check Price
ECE standard (Europe & worldwide). Single-filament signalling bulb with BA15s bayonet base. 12V, 21W.P21WCheck Price
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 21W.199Check Price
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W.1034Check Price

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