Well I went on and ordered a eurospare heater core this morning. Was going to bypass but my girlfriend didn't like the idea of no heater through the winter. Also went ahead and ordered a Motorad 439-180. My only question with it is that all the ones I looked at said they fit a 99-02 but not 03-04 I didn't see a difference between my 99 and 04 that would cause it not to fit my 04, am I missing something?

 

Heater core from AB says 99-04 so I assume the one you bought should be fine.

 

99-02 is the same as 99-04. And actually the DII shares the same heater core with the DI.

When you really start digging in be sure to take care of the metal heater pipes. It's made of a very soft metal and can get nicked quite easily.

 

You will "discover"" that the truck is built around the heater core. This is not a two hour project.

 

I guess I should have been more specific, sorry about that. The heater core said it was for a 99-04, it was the motorad thermostat that I could only find 99-02.