LED Trailer Lights Don't Blink When Headlights On
 

So I don't get too chatty, I'm just going to go through a list of everything (also, 2001 Silverado if needed):

The trailer is a custom made mobile home frame and the wiring is just standard four-wire trailer wires with a 4way flat end.

I cleaned the ground on the pigtail end. I cut all the butt connectors off and installed new ones and made sure to seal them from the weather.

All the trailer lights work as expected when the truck's lights are off.

When I turn the headlights on, the trailer lights will turn on, but when I use turn signals/hazards, the just illuminate brighter without blinking. Brake lights work fine, just no turn signal blinking. I should also note that through all of this, the lights on the truck always work fine, all brakes, turn signals, etc.

The housings on the trailer are old style round that use 1157 bulbs (dual filament bulbs for brakes and turn signals). The LED bulbs I'm using are LASFIT 1157 standard, not the ones with the built in load resistors.

I can plug the original incandescent bulbs and everything works fine, it's just the LED bulbs acting up when the headlights are on.

I have a set of LED towing lights and those work fine no matter what the truck is doing.

Dad's 2020 Colorado does not have this problem.

I am using a 7way to 4way adapter. Any other trailer I hook up, whether incandescent or LED, work fine.

LED load resistors stop hyper blinking, but would they do anything different in this case?

Also, I have noted that Silverado's dim the turn signal bulbs when the running lights/headlights are turned on, could this also have something to do with it?

I haven't contacted LASFIT yet about this, I wanted to see if maybe there was something I was doing wrong or something I could do to make it work. I wouldn't rule out some issue with the bulbs not being 100% compatible or maybe there's some load issue being so far away from the truck.

Any ideas or is this just the way it is?