So I have finished wiring and installing my 12 inch sub in the access cab. After getting everything powered and fused, I turned it on and I am very impressed. This post is due to the hundreds I have read basically bashing stock headunits that cause impotent subwoofers.
I bought the major components used to save money.
Scosche 4 channel RCA line converter 20.00
JL CL-RLC Line driver 30.00
JL 500/1v2 amp 300.00
JL 12w6v2 subwoofer 100.00
Sealed enclosure (building a new one to better fit the access cab free
4 gauge wiring with 60 amp fuse 30.00
12 guage speaker wire 5.00
The big issue people complain about is a lack of voltage from the deck
to the rear speakers, not enough to make the subwoofer work.
I can confirm this is true, I was getting 0.3v arriving to my amp.
The line driver was installed and now I keep it at 6v.
Honestly this thing can be heard blocks away if that is your thing. I have mine tuned so as not that loud. I like my 6 disc stock deck that I bought off a user on here despite its shortcomings.
If anyone is considering this setup I highly recommend it. One subwoofer on a stock system is incredibly popular due to the simplicity. Install was a breeze and I used some writeups on here for disassembling the interior to run wires.