Replace OEM JBL sub and add an amp?

So I have a 2018 with the JBL system. I looked behind my drivers side rear seat, but I didn't see any sub. Am I missing something?

 

Passenger side behind rear seat. You’ll see a grill, but the sub and amp are behind the plastic

 

I looked on that side too. I just have pocket , no grill. Is it possible my truck came with the JBL system amd no sub?

 

Actually I am mistaken, it is my old truck I am thinking of. This one has the grill behind the passenger rear seat

 

there's your sub lol

 

Ya, sorry about that. Still having flashbacks of my 05.
Anyway , this is a good thread. I am surprised that no one talked about the idatalink module in this thread or maybe I missed it

 

As far as I know with the Maestro, you have to buy the data link along with having to piece meal together the rest of what the JBL amp integrates including back up camera, rear lights, navigation, steering wheel controls etc. to retain the head unit, the easiest route for us folks with jbl is to use amp pro and keep the jbl amp in place for everything else except audio. If you are changing your head unit, then Maestro is what you need. Some people hide the jbl amp in the cubby under the rear seat, I just integrated it into my amp rack.

There is lots of good help on here on how to do this. If you have any questions hit me up. This install does take a fair amount of planning and education to understand what is going on with the FUBAR jbl system, so I would start with the wiring diagram to help understand things, then look at what Amp pro vs Maestro will offer you.

and yes the ap4-ty-12 will work with 2018 Tacoma with jbl even though it is not on the list of compatible vehicles.

 

Thank you. My concern was where to put the stock amp if I used the PAC. I am getting a box that takes up all of the behind the rear seat area. I never thought of putting it in that little cubby hole under the seat. Does this PAC unit go behind the head unit? If so, is there a decent amout of space or is tight.
Last question, since you keep the factory amp in place, do you run new speaker wires to each speaker or is there a different adapter to grab the speaker wires at the factory amp. Thanks for all the help! I have read tons of thread on here, but just got more confused the more I read...

 

$37 APH-TY04 Speaker Connection Harness

APH-TY04 harness

 

Perfect, Thank you. So I guess you grab the wires at the AMP.

 

yep. this harness lets you wire your new amp straight into the factory speaker wires, while also keeping the JBL amp up and running

 

Does that Pac unit go behind the head unit?

 

Yes the PAC AmpPro fits behind the head unit. There is plenty of room to fit that with the giant harness you have to stuff down there. I would suggest getting RCA cables with small heads on them to save a little room

 

Now I just have to decide on amp placement and more importantly , go with 1 single 12" and a 5 channel amp. I think I could fit the amp were the stock sub box is, everything would be neat and hidden .
Or
The new TT custom 2 12" fiberglass sub box that takes up behind the entire rear of the seat. Then I would have to us 2 amps. One could go in each cubby or underneath the drivers seat on TT amp rack.
It is a hard decision.... money isn't playing a factor into this, just good sound.
I use to have a 93 Cobra, I built a boundary loading box with 1 polk db 10" in it in the spare tire area. It hit like 2 12"s. But also sounded great with country music. I miss that bass, but not sure 2 12"s in a regular sealed box will make the same sound. I am a little afraid of muddy bass.

 

A single 10 or 12 is enough for the volume of the cab if you are going for SQ. Check out sundown sd-3 10” or JL has a good shallow mount or even the IDQ-10. This is what most of the guys on here are running if it’s not Kicker.

 

I had the JL Stealth box with 2 10"s in my 05 double cab. It was horrible, definitely not enough bass as all.

 

So I decided to just go for it... 2 12's and a Rockford Punch P600X4 for interiors and a Punch P1000X1BD for the subs...
I am not worried about loosing space behind the seats, so I figured ton just go for the 2 12's. Worse case I can take them out and go with 1 12" because that amp 300W RMS @ 4ohms, 600W RMS @ 2ohms and 1000W RMS @ 1ohm. I will be running it at 1ohm for the 2 12's

 

You won't regret those amps. A little pricey but absolutely worth it. I threw mine under the driver's seat with spacers and I'm about to do the same on the passenger side.

Heres an idea for mounting the stock amp in the underseat cubby. I just had to extend 2 wires that I assume go to the 3rd brake light

And if you're going with two 12s, I'd definitely throw some 3/8" spacers behind the back seat bolts to push the bottom away from the subs. Heres an idea of how much those spacers give you some peace of mind

 

That is an impressive install! What adapter do you use the pac?
I am still waiting to get in touch with idatalink like to confirm what theirs does and does not do.
I will definitely use those spacers on the back sweat, that is a great idea. How exactly did you mount the amps underneath the front seat?

 

I appreciate it. It's a very long process but absolutely worth it every time I drive the truck. What adapter are you referring to? This is what the AmpPro looks like tucked behind the HU

For the amp install, I used two 2x4s and cut them up to fit like puzzle pieces under the seat and heavily glued them to the floorboards before screwing the amp into the wood. Unfortunately I didn't take pictures of that process but if you're interested I have more pics and details in my build thread. https://www.tacomaworld.com/threads/3rd-gen-jbl-subwoofer-upgrade.572040/