Audio Systems: Infinity sound system, dodge ram quad cab, ram quad cab

Question
I own a 2004 Dodge ram quad cab with the infinity sound system what size are the back door speakers? I know the front doors have 6*9 in them want to replace all speakers.

Answer
I must know more about the vehicle to know for sure.  Which model truck? 1500 or 2500, etc.?

But, the rear speakers are round, not oval, and are a little smaller than the standard 6.5" - I think.  But here is what you should do:  Go to www.crutchfield.com and work through the "outfit my car" sequence and they will lead you to speakers that will fit and tell you the modifications that are necessary to make a standard speaker fit the hole/opening.

Let me know if you get stuck.

PS:  Outfit my car can be found  at:

http://www.crutchfield.com/cgi-bin/autoinfo/autoinfo.asp?lp=%2fapp%2fCar%2fMyCar...