Wow. Thanks for the quick response guys! I'm sorry I didn't get to this sooner, but I really appreciate the suggestions. You are all very helpful, and this sure is a lot of information. I'm looking at these pictures now and I realize that they are TERRIBLE. I'm embarrassed. Hopefully the blinker ones give you some idea of what's going on. I'll give him a wash soon and take a picture of him shining in the sun.
Bloo:
They are separate add on housings, I'll include pictures here. I think you also want pictures of how the wiring works, but I didn't get those last night. Next time I get a chance I'll try to take some photos.
The bulbs we are using are labeled "GE 1129 J7", which seem to be 6v when I look online. Looks exactly like the one you mentioned.
I do think that it is an electrical problem since now that I've been experimenting with them more, I've noticed that they are also very erratic, sometimes with longer flashes and sometimes shorter. I think the longer ones get brighter, almost like the circuit is not active long enough for the bulb to get to full brightness before it cuts off again, I wonder if that has something to do with it. Does this make sense? Have you ever heard of anything like that? Painting the inside of the housings sounds like it would help, that's a great idea. I'll keep that in mind if we can't figure this out.
Also. Could you please explain how to run a ground wire? What kind of wire do I need? Should I just make sure it's making contact on either end or do I need something that grabs on like a jumper cable head? I'm sure it's obvious that I have no idea what I'm doing, and if you could point me to some online resource instead of explaining that would work as well. Thanks again.
Rodney:
The connections all look pretty clean, I'm not really seeing any corrosion. When I get a chance I'll figure out how it all connects and pull things apart to clean them.
How do you test a bulb on the battery? I tried pressing the bottom against the battery when the truck was running, but nothing happened. I'm not really sure how else to realistically use the battery to test a bulb like you're saying, could you please explain that to me? Thanks.
The flasher is definitely correct and seems to be working. We replaced it a while ago with a heavy-duty flasher to see if it would fix the problem, and no luck. I still have both and they work the same.
Ben:
Here are some pictures! Like I said above, I will work on cleaning the connections next time.