Does anybody know what size speakers are in the door of a 90 D150? I want to change them out

 

Mine are 6x9s but to be sure you can call Crutchfield and ask them. 1-800-555-9430

 

i think i have 6x9's in the doors on my 91 but i know someone cut the holes bigger to fit them because they did a poor job cutting the holes bigger

 

some late 80's early 90's also used i think 5 1/2 inch.
got a door from boneyard for my 93,and it had factory 5 1/2 inch,it was from a 1990. good luck

 

My doors had 6X9's also. I would go with 6X9 and use the template that comes with it and cut to fit if need be. If you want an exact fit, the only way for sure is to pull a door panel. It's not hard to do and if your going to change them out it will have to be done anyways. Best to use polypro instead of paper speakers since they are moisture resistant.

Something that I did was find some factory speaker grilles from the salvage yard that go tucked away neatly in the pillars behind the seat and above the seatbelt retractor mechanism. They are made for 4X10's but I fabbed an old set of 5X7's to fit pretty easily. If you do this, don't block the notch that is on the side of the grille so that it skirts the door striker pin back plate. I made this mistake on my first attempt. I just used some left over aluminum window screen frame for spacers and self tapping screws.