XLT 302a LED Tail Light Bulb Saga & Solution

stangsandatruck

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So i ordered the tail light kit from Diode Dynamics for the 2015-2021 F150. The kit included 4 7443 bulbs. Went to install them and they did not fit, so I reached out to DD. I worked with them to get the specs of the 302a bulbs - which the measurements state its a 4257. Turns out the 4257 the same as the 3157 where you need to cut the tabs off the 3157. For Diode Dynamics - I was told that the tab modification would not void the warranty (3 years) and I’d have no issue if they were exchanged and missing the tabs. I intalled them and they do work great. The fitment is tight so the bulbs will not flicker or come out. Overall a great modification to the truck - you can really tell the difference between the stock and the LED upgrade.

TLDR - If you have the XL or XLT w/ BLIS - don‘t order the kit from DD. Order 4 3157 bulbs and modify the tabs to fit the socket.

Side note - the team at Diode Dynamics was great to work with directly, they even offered to send a few different bulbs if the modified 3157s did not work. The bulbs were quite expensive, but the customer service was great in getting me the correct bulbs, so it was worth every penny.
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Whoskyle

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So i ordered the tail light kit from Diode Dynamics for the 2015-2021 F150. The kit included 4 7443 bulbs. Went to install them and they did not fit, so I reached out to DD. I worked with them to get the specs of the 302a bulbs - which the measurements state its a 4257. Turns out the 4257 the same as the 3157 where you need to cut the tabs off the 3157. For Diode Dynamics - I was told that the tab modification would not void the warranty (3 years) and I’d have no issue if they were exchanged and missing the tabs. I intalled them and they do work great. The fitment is tight so the bulbs will not flicker or come out. Overall a great modification to the truck - you can really tell the difference between the stock and the LED upgrade.

TLDR - If you have the XL or XLT w/ BLIS - don‘t order the kit from DD. Order 4 3157 bulbs and modify the tabs to fit the socket.

Side note - the team at Diode Dynamics was great to work with directly, they even offered to send a few different bulbs if the modified 3157s did not work. The bulbs were quite expensive, but the customer service was great in getting me the correct bulbs, so it was worth every penny.
I did this mod but ordered the 3157, 4 for 10 bucks on Amazon and it worked great!! Also I changed out the front side marker light bulbs for LED as well, since for whatever reason on 302A the headlight assembly itself is LED but side marker and turn signals aren’t
 

Melly

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I did this mod but ordered the 3157, 4 for 10 bucks on Amazon and it worked great!! Also I changed out the front side marker light bulbs for LED as well, since for whatever reason on 302A the headlight assembly itself is LED but side marker and turn signals aren’t
What's the number for the side
marker and turn signal. Thx
 

jordandev

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stangsandatruck

stangsandatruck

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I also replaced the front signal lights. 4257 / 3157 in yellow is what I used. I just ordered the side markers and they are a 194 LED.
 

djdj1000

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Thank you so much for sharing your experience! I have been looking for this information for the last few weeks, and checking with DD on the specs for the 402A.
 

moates

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So i ordered the tail light kit from Diode Dynamics for the 2015-2021 F150. The kit included 4 7443 bulbs. Went to install them and they did not fit, so I reached out to DD. I worked with them to get the specs of the 302a bulbs - which the measurements state its a 4257. Turns out the 4257 the same as the 3157 where you need to cut the tabs off the 3157. For Diode Dynamics - I was told that the tab modification would not void the warranty (3 years) and I’d have no issue if they were exchanged and missing the tabs. I intalled them and they do work great. The fitment is tight so the bulbs will not flicker or come out. Overall a great modification to the truck - you can really tell the difference between the stock and the LED upgrade.

TLDR - If you have the XL or XLT w/ BLIS - don‘t order the kit from DD. Order 4 3157 bulbs and modify the tabs to fit the socket.

Side note - the team at Diode Dynamics was great to work with directly, they even offered to send a few different bulbs if the modified 3157s did not work. The bulbs were quite expensive, but the customer service was great in getting me the correct bulbs, so it was worth every penny.
Forgive my ignorance guys, these won’t throw any codes? Or would I need resistors or will these bulbs work with out anything else? Thanks in advance!
 

Whoskyle

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Forgive my ignorance guys, these won’t throw any codes? Or would I need resistors or will these bulbs work with out anything else? Thanks in advance!
They will, but you can use forscan to disable
 

djdj1000

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FYI- it sounds like if your truck has the BLIS system equipped, the tail lights might be sealed units and won't have bulb interchangeability.
 
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stangsandatruck

stangsandatruck

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FYI- it sounds like if your truck has the BLIS system equipped, the tail lights might be sealed units and won't have bulb interchangeability.
I have BLIS on my 302A truck. If you have a 402a+ truck - you already have LED tail lights. The 100A - 302A trucks all use standard bulbs to get the job done. The 100A - 302A trucks w/ BLIS (copilot 360) use the 3157/4257.

I am not sure about the bulb sizes in non-BLIS trucks which would only be XL / STX models without copilot 360.
 
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stangsandatruck

stangsandatruck

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Forgive my ignorance guys, these won’t throw any codes? Or would I need resistors or will these bulbs work with out anything else? Thanks in advance!
As @Whoskyle said - use forscan to disable the hyper flash on the dashboard. Even after you put LEDs in the housings the lights themselves did not change flash speed. The new trucks don't use typical mechanical relays so they won't hyper flash like old vehicles and makes a resistor not necessary either. It's a digital type relay that controls flash rate, it may even be the body control module that actually does it.

When using forscan - there is a code thrown for open circuit in tails / front signals, but no lights will be shown on the dash. A typical generic code scanner usually doesn't search for this code.
 

JCM

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TLDR - If you have the XL or XLT w/ BLIS - don‘t order the kit from DD. Order 4 3157 bulbs and modify the tabs to fit the socket.

Side note - the team at Diode Dynamics was great to work with directly, they even offered to send a few different bulbs if the modified 3157s did not work. The bulbs were quite expensive, but the customer service was great in getting me the correct bulbs, so it was worth every penny.
Thanks for this post. Any reason to go with 3157 bulbs from Amazon or elsewhere vs going with DD, aside from cost?

Also, did you do the white reverse lights or just the 4 red lights? I'm getting conflicting information if those are 3157 as well or 7443
 

Blueshound

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Thanks for this post. Any reason to go with 3157 bulbs from Amazon or elsewhere vs going with DD, aside from cost?

Also, did you do the white reverse lights or just the 4 red lights? I'm getting conflicting information if those are 3157 as well or 7443
+1
Would love brighter reverse lights, especially if no forscan required.
 

Graygoose2021

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For my STX, I see they have several ones mentioned on reverse lights, I didn't even think about swapping the red ones too...hmmm
 
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