We have a 1991 Dodge W250, Diesel, Manual, LE trim, bought new, and at some point during the mid 90s, both doors were worked on, something to do with the latches, but ever since then you have to open a window to get the door to close all the way. If you don't, you end up with a half latched door, and your ears pop. This happens regardless if the cab fan is running or not.

I assume there is some type of cab exhaust vent, like on GM and Ford vehicles, and I am assuming it is in the door, but I haven't found anything on it.

Where is it, and what is probably wrong with it?

 

I had a 90 and in back of the door below the latch there is a vent with a flap.

 

I know my '93 has it.

I'm impressed with my '90 for it's seal-tightness! I leave the windows open 3/8" so its not really an issue.

 

I think there are vents in the door area. At least you know your cab doesn't leak. You might make sure your air is set to regular and not recycle. This might be an issue if you have it on recirculate.

 

Chevrolet had a better idea for 1991 .... they vented the roof.

 

It's called an "Exhauster" #1.
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