I didn't check anywhere to see how much it would cost or the hours it would take.
It took me 3.5 hours to change myself after a freind disconnected the a/c and I'm a carpenter!

 

So how big of a PITA was it? Did you have to pull the whole dash apart to get to it?

 

drop the steering column, pull every panel with a switch, button or lever. pull the glovebox, ashtray, cupholder and panel directly behind windsheild. Then you take out approx 4 bolts form each side, 4@ the wind sheild an 2@ the center hump. Unhook a/c and heater lines,4 or 5 bolts holding heater box ( 2 bolts in engine compartment). Take heaterbox out passenger side and there is your heater core.
Yeah its a pain in the A!

 

I figured it was from all I've read about doing it on these trucks. All you can do is keep you flushing and refilling your coolant at recommended intervals and hope it doesn't crap out on you.