jdyates
Ghetto Racetruck
When i was doing research for bulb numbers and such for my LED conversion, I found TONS of info for the 95-98 interior/trucks, but no consistent/useful info for the 88-94's like mine. Here is what I've gathered (and successfully tested) so far.
For future reference, pay attention to the number at the end of the four-digit bulb numbers. "6" means single intensity (always in "high" mode, like the under-dash lights), and "7" means dual (high AND low, such as turn signals)
Also, the ones that start with a "1" (such as 1156/1157) are CIRCULAR base bulbs, and the ones that start with a "3" (3156/3157) are the FLAT-BASE bulbs.
Front parking lights/Turn-signals: 1157
Front corner lights (reflectors): 194
Under-hood lights: 1156
Two bulbs under dash, pointing down towards floorboard: 1156
Gauges: 194 (SEVEN of them, unlike the SIX for the 95-98 trucks) plus the twist-locks for them, since the stock bulbs are soldered into the twist-locks (can be found on SuperbrightLEDs.com for cheap)
Dome light: 578 Festoon Style bulb
Map lights: These are the festoon style with the little hooks on either end, don't have the bulb number since i didn't replace mine.
STOCK GM TAIL LIGHTS: For the 88-89 trucks, they are 1157 for the top two bulbs, changed in '90 to the 3157 and 3156 for reverse (thanks 88GMCTruck for that info!) EDIT: Paragraph removed until i can do some hands-on testing on the circuit boards, should be re-written within a day or two!
Let's continue...
Reverse: You can use either a 3157 or 3157 in this spot, doesn't make a difference (I am running 3157's and they work great), BUT, be aware of the limited space behind the reverse lens, don't order a (for example) 82-SMD bulb, it is very long and WILL NOT fit.
License plate lights: I have been told by multiple people that these should be 194's, but i pulled mine apart and found 1156-base bulbs. CHECK BEFORE YOU ORDER. Here is what my plate lights look like (kinda hard to see, but looks like the wires were cut then re-spliced together, therefore i have reason to believe that my plate lights are NOT OEM)
But as i mentioned before, TAKE THEM APART and check for yourself, just to be safe!
Oh, and just a little bonus fact, if you plan on installing an LED tailgate bar, the proper size is 60" bar for the fleetside (straight-bed) trucks, and 49" for the stepsides.
As I mentioned before, it is possible that your bulb numbers DO NOT match up with mine (maybe your truck's previous owner spliced in a different socket for a certain bulb for convenience) so i urge you all to DOUBLE-CHECK before you order bulbs. I am not responsible if you order the wrong bulbs because you didn't check before you order.
For future reference, pay attention to the number at the end of the four-digit bulb numbers. "6" means single intensity (always in "high" mode, like the under-dash lights), and "7" means dual (high AND low, such as turn signals)
Also, the ones that start with a "1" (such as 1156/1157) are CIRCULAR base bulbs, and the ones that start with a "3" (3156/3157) are the FLAT-BASE bulbs.
Front parking lights/Turn-signals: 1157
You must be registered for see images
Front corner lights (reflectors): 194
You must be registered for see images
Under-hood lights: 1156
You must be registered for see images attach
Two bulbs under dash, pointing down towards floorboard: 1156
You must be registered for see images attach
Gauges: 194 (SEVEN of them, unlike the SIX for the 95-98 trucks) plus the twist-locks for them, since the stock bulbs are soldered into the twist-locks (can be found on SuperbrightLEDs.com for cheap)
You must be registered for see images
Dome light: 578 Festoon Style bulb
You must be registered for see images attach
Map lights: These are the festoon style with the little hooks on either end, don't have the bulb number since i didn't replace mine.
STOCK GM TAIL LIGHTS: For the 88-89 trucks, they are 1157 for the top two bulbs, changed in '90 to the 3157 and 3156 for reverse (thanks 88GMCTruck for that info!) EDIT: Paragraph removed until i can do some hands-on testing on the circuit boards, should be re-written within a day or two!
Let's continue...
Reverse: You can use either a 3157 or 3157 in this spot, doesn't make a difference (I am running 3157's and they work great), BUT, be aware of the limited space behind the reverse lens, don't order a (for example) 82-SMD bulb, it is very long and WILL NOT fit.
License plate lights: I have been told by multiple people that these should be 194's, but i pulled mine apart and found 1156-base bulbs. CHECK BEFORE YOU ORDER. Here is what my plate lights look like (kinda hard to see, but looks like the wires were cut then re-spliced together, therefore i have reason to believe that my plate lights are NOT OEM)
You must be registered for see images
But as i mentioned before, TAKE THEM APART and check for yourself, just to be safe!
Oh, and just a little bonus fact, if you plan on installing an LED tailgate bar, the proper size is 60" bar for the fleetside (straight-bed) trucks, and 49" for the stepsides.
As I mentioned before, it is possible that your bulb numbers DO NOT match up with mine (maybe your truck's previous owner spliced in a different socket for a certain bulb for convenience) so i urge you all to DOUBLE-CHECK before you order bulbs. I am not responsible if you order the wrong bulbs because you didn't check before you order.
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