Question about amp and sub ...
 

Does the stock HU on a 2010 f150 XLT have preamp outputs.

I want to keep the stock HU and probably the stock speakers but any base on these speakers make it unbearbly distored. I'd like to add an amp and a 10" sub to my regular cab. Maybe down the line, i'll upgrade the speakers.

my guess is no? They normally don't, is there any other manufacturer out there that has them on their factory radios? The 04-08 F150 radios did not. So you'll need a line output convertor or an amp with speaker level inputs. I installed such an amp along with a sub in my 04 F150 w/factory radio and it sounded just fine.

if you research a little bit i believe you can find an adapter that goes between your factory radio and the wire harness that will allow you to hook up to your amp... my friend did this to his mustang so he could run an amp and sub but keep his stock radio. hope this helps,
Q.

i believe something like this should work as well as improve the overall sound of your bass.

MTX re-Q5 5-channel bass restoration signal processor Get full bass response when adding amps to a factory system at Crutchfield.com

From what I can tell I'll probably have to get a component that will take the speaker signal and change the signal to be used with an amp.

There are some forums reporting that trucks that have the sub option with the sony speaker package may have a sub harness in the vehicle but this would be on lariat or better packages.

A line out converter is your best bet to keep the stock head unit, but that isn't going to give you nearly the quality of an aftermarket with preouts. You'll notice a bigger difference by upgrading your speakers so they can actually output the low freq stuff. That stock headunit (non-Sony) is actually pretty nice, it's just that the paper speakers are crap.

The speakers arrive today and I'll put them in this weekend. Then I'll be deciding on whether or not I'll be buying the rest of the system.

The plan is a Kicker 5 channel amp with an MTX REQ5 and a single 10 inch sub.