My sub in the rear blew. I'm trying to find out how to remove the speaker, and what size the speaker is. If possible, I just want to take the speaker out and put a new one right back in quickly. Thanks in advance

Don't work? Sounding bad? Or no sound? It's possible just a plug on the head unit came off. Possible someone played with fader. The worst cases are you blew the drivers out or blew the rear stage of your deck out.

if you short a sub it will hum try connecting it to a working speaker (no amplifier) if you have access to rear of sub check for wire only needs to be the size of a hair arcing out the speaker, i have a sub that does that on only one output (left rear) its actually the stereo causing it to hum..

2001 Mitsubishi Galant Car Stereo Radio Wiring Diagram
Car Radio Constant 12v+ Wire: Red/Black
Car Radio Switched 12v+ Wire: Blue
Car Radio Ground Wire: Chassis
Car Radio Illumination Wire: Green/White
Car Stereo Dimmer Wire: Black/Yellow
Car Stereo Antenna Trigger: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Front Speakers Size: N/A
Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): White/Blue
Left Front Speaker Negative Wire (-): Black/Blue
Right Front Speaker Positive Wire (+): White/Red
Right Front Speaker Negative Wire (-): Black/Red
Rear Speakers Size: N/A
Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Yellow/Blue
Left Rear Speaker Negative Wire (-): Gray/Blue
Right Rear Speaker Positive Wire (+): Yellow/Red
Right Rear Speaker Negative Wire (-): Gray/Red

The manual... http://www.retrevo.com/support/Denon-AVR-2310CI-Receivers-manual/id/23452bh638/t/2/

I'm pretty sure you mean "LFE + Main".

You need to identify the speakers to the receiver as Large or Small regarding their bass-handling capacity more than their actual size.

"LFE" removes the possibly overloading bass in a given speaker channel containing 'small' speakers and sends it to the subwoofer.

"LFE + Main" is sort of explained on page 29 "Bass Setting". The intent of LFE+Main is to task your subwoofer with the bass that ALSO exists on all other speaker channels regardless of their ability to handle it all by themselves. As you can imagine, this might make the subwoofer respond to sonic events that are actually supposed to be directional from, say, the rear channel(s). In that case the event might seem to come from wherever the sub is located instead of the intended direction; or at the very least it might seem to come from both places which is probably not what the sound engineers intended when they recorded the piece.

Having full-range speakers 360-degrees around PLUS a subwoofer, I don't subscribe to the 'bass-is-non-directional' school of thought. If you've ever felt the concussion from and subconsciously glanced toward one of the speakers after, say, a huge explosion, the system is working.

Possibly, try a search engine.

But even if you find one you're stuck with the same dedicated amp.

I once had a powered sub that blew its internal amp and the store gave me a whole new sub. THAT one blew the same way so I disconnected the internal amp and now use it as a passive sub with a separate amplifier that I own. Separable amp/speakers allow for the surviving component to be redeployed.

You probably blew out the sub, the larger speakers are more at risk to distortion are high output levels. The amp can no longer maintain its true output and begins passing voltage to the sub and the cone over travels or the winding burns out. You can try gently pushing on the sub membrane to see if it moves in and out easily, it may be stuck and you can free it up. If that doesn't work, remove from system and check the coil with an ohm meter resistance. it should read a low ohm value. If high value, it's blown and you need a replacement. It is also possible you blew the network that sends the lows to the sub and the high to the mid range and tweeters, check the sub first.

2000 Ford Expedition Car Radio Wiring Diagram
Car Radio Battery Constant 12v+ Wire: White/Purple
Car Radio Accessory Switched 12v+ Wire: Black/Pink
Car Radio Ground Wire: Black/Green
Car Radio Illumination Wire: Blue/Black
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger Wire: N/A
Car Stereo Amp Trigger Wire: Blue
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: 6′ x 8′
Car Audio Front Speakers Location: Doors
Left Front Speaker Positive Wire (+): White/Red
Left Front Speaker Negative Wire (-): Brown
Right Front Speaker Positive Wire (+): Green
Right Front Speaker Negative Wire (-): White/Orange
Car Audio Rear Speakers Size: 6′ x 8′
Car Audio Rear Speakers Location: Rear Doors
Left Rear Speaker Positive Wire (+): Light Blue/Black
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Purple/White
Right Rear Speaker Negative Wire (-): Light Blue

4 nch in the front and 6 1/2 rear i believe 8in free air sub you can use a 10in sub with little modification.. this answer was taken from a lexus owners forum, another answer said 4inch in front and the rear, but both say 8 inch sub.

250v 1A fuse

If no warranty - remove amp and check sub to another amp to isolate speaker from internal amp. Either the amp blew a channel or subwoofer blew. JBL's are typically well built. Has this speaker often been pushed loud often?