2003 f150, problem with subs

if the wires in the box are  soldered then check the rcas add a new  set of  rcas and see what happens. i doubt its the speaker box termianl unless the springs on them are old unless its not spring loaded. but most of the time its a loose connection.

When you checked the voltage at the amp, was the amp playing at volume 35?   What load is the amp seeing?   Do you have all 4 voice coils wired in parallel?  What ohm coils do the speakers have?   There is a missing designation on the description of the woofers.  W3v2-D#     the missing number will tell you what ohm the coils are.  What is the minimum load of that amp?

the gains is at 3 clicks..its barely above minimum, and they are w3v2-d4...the minimum load is is 2 ohms on the amp...and i have them wire to 4...