I have an 08 non-Bose setup with a blown door sub. Can I put a aftermarket flat mount sub in it's place. Really don't want to go back with the trashy factory speakers!

You still have a factory amp in the car for the subs in the door. Take a multimeter and measure the ohm of the factory woofer. If you dont put the same ohm woofer in there you can blow the amp or the amp will not give out the same power.

Check on Ebay, you might get lucky finding a replacement sub. Even if you match the impedence of the factory amp with an aftermarket sub, it's still good to have a matching set.

I think a chucked mine in the trash. I will look today...if I have it you are welcome to it.