I am swapping transfer cases and the case I have must be for an 03 instead of an 04. It has different plugins according to my mechanic. Would we be able to swap the cover from one unit to the other to make this work?

 

Not 100% on this one but your mechanic might be seeing that the CDL has no place to link up becuase the 03 does not have CDL in the T-case but the 04 does have it, so it's logical to think that you'll have some shifting components from the CDL hanging down that now have no place to go. Aside from that I don't think there are any difference between the two cases but I'm sure someone else will chime in on this.
Good luck.
If you've never used your CDL, this is not a big deal but if you do use your CDL then you might want to even return this T-case and look for a 99,2000, 2001 (first half of the year) and the 04. They all have it. Confused yet?

 

No, it has the CDL, it is the sensor conections that are the issue.

 

Then it is not an 03 case cause they didn't come with CDL, must be an early 99 thru 2001 case, and yes you will need to modify the connection.

 

04 has two CDL locked switches that then the light on.