The above picture is with only the parking lights (the switchbacks) illuminated - not the headlights)

These bulbs are impressive in several ways. They have those “fingers” or “claws” that not only make them look...well...armored, but they also look sort of mean. The base is notched just like the OE glass bulbs, but lacks the key that is present on the OE bulbs. I therefore assumed I’d have the 50/50 polarity dance to perform...but both LH & RH bulbs worked on the first try. I therefore assume there is no polarity issue, which is refreshing. The notch across both sides of the base is securely gripped by the contacts in the socket - these bulbs will absolutely not be found rattling around inside the headlamp housing!

Unlike some vehicles, the lens for the turn signals on the ‘19 F-150 is diffused (like a bathroom window) which means you cannot see the bulb when you look into the lens from the front. I was therefore apprehensive that the irregular lens would take away from the “mini-headlight” effect that I was hoping for. But that turned out to be a non-issue, because these bulbs are much more than tiny [front-facing] spotlights; they have emitters on the sides as well as in the “nose”...which fill the reflector with a truly impressive & cool white light. Result: exactly what I was hoping for: bright, white mini-headlights.

The amber signal works as its supposed to - flashing on/off/on/off (as opposed to on/white/on/white)

I opted not to purchase the resistors; partly as a roll of the dice, and partly because - even if they flashed a little fast[er than OE] - I don't mind. However, I may relent, because they flash very fast.

Overall I am very happy with my purchase from GTR Lighting!

 

Same as the Profile Peak which I had and are junk, you'll be lucky to get 6 months out of them.

 

What did you replace them with? My turn signals and high beams are all the only non-LED lights left on the outside of my truck so they're on my to-do list.

 

eek! Hopefully the GTR's are better quality, and/or they have improved the technology in the recent past.

 

Lasfit on Amazon. Already burned through a set. I will be switching them out to Diode Dynamic soon, they are the best, but money was tight since my wife has the summers off.

 

Profile Peak makes a 4257?

 

I didn't say that did I? I said "same as" meaning the housing, shape of bulb, etc. Because of the look, they are all probably made in the same Chinese factory.

 

I think he is asking because there aren’t that many options for that bulb size .. I think he really meant to ask if DD had that bulb size.. then I could be totally wrong

 

My point is, with any led bulb, if they look exactly the same, regardless of size, they are probably made in the same Chinese factory. I doubt the GTR quality is any better than the Profile Peak. I posted a video of my Profile Peak going crazy, even sent the video to The Retrofit Source. I swear, they will never see another singe $ of my money. They sell junk and yes, I mean Morimoto as well. Spend some time on lighting forums, Morimoto isn't all its cracked up to be, especially mini-bulbs. If its budget based, get it off ebay or Amazon, or for lasting quality, go Diode Dynamics or Sylvania/Philips/ZEVO (but no switchback options for those 3).

 

my gtr's are over a year old and still working fine