almost every sound shop I've been to has told me JL audio W1s for under the seat, I just ordered 2 10" off amazon for 99 bucks a piece so we'll see

 

A buddy of mine custom built a ported box for a regular 10" without having to lift the backseat.

 

I just put a Polk MM1040 shallow sub in a supercrewsound custom underseat box, powered by a Kenwood 8105 mono amp behind the rear seat. Looks factory, sounds awesome, and I kept the stock head unit which was the most important thing to me.

 

How big is the box you got it in? I got one and it sounds hollow.

 

Fox makes a sealed box that can fit 2 JL10w3. I haven't yet bought it for my truck. Soon but the reviews on the box are good. I believe the box cost around $120