I've been having trouble with my tail lights, i bought all new bulbs both 1156 and 1157. i think what i have right now is just my tail lights light up while i have no blinkers. is there anything i can look at or check before following my wires all the way up? My front right blinker will work and the arrow in the dash will blink like it should. when i turn on my left blinker the dash light just stays on without blinking and neither light blinks.

 

Did you check the left front parking light bulb? On these trucks, if a light is blown, the t/signal won't flash on that side. On the rear, check the grounds first. That tends to be a common problem with these trucks.
Report back and we'll go from there.

 

Same taillamps/sockets: 1974 F100/350 Stylesides from serial number T80,001 / 1975/79 F100/350 Stylesides / 1975/91 Econoline / 1978/79 Bronco.

 

checked the front light on the left and it seems to be fine. the only turn signal i have is the front passenger side i don't know what to do

 

I have a '78 F150 with this problem as well, I ended up having to replace both rear tail light sockets. I also took apart all four grounds and used a stainless steel brush to clean the attach point and ground wire terminals. Lube them with dielectric grease and reassembled. Works great.

 

yeah i think my sockets will need replaced soon. i got everything to work except front drivers side.

 

It's pretty easy. And fairly cheap. $5 for the socket. And a couple wires.

 

Just a heads up,
If you buy aftermarket replacement sockets, make sure they don't space the bulb to close to the tail light lens or it will melt a hole in the lens.