How to replace heater core in 2003 chevrolet truck

SOURCE: heater core on a 2003 Chevrolet pickup 4 wheel drive crew cab

if you have air conditioning you will need to take it to a garage and recover the r134, you will need to remove the dash to allow you to remove the heater box, it's an ugly job, I've done a dozen or so and can do it in about 6 hours now, the first time it was closer to 11 hrs, good luck

SOURCE: 1998 chevrolet k-1500 heater-core replacement

Remove the heater hose clamps and the hoses from the engine side of the firewall. From the inside under the dash on the pass. side, remove the lower panel screws and slowly pry the lower cover down and the heater core will slide out of the heater box. Installation is reverse of removal.

SOURCE: 1999 S10 Chevy truck

you will have to remove the dash assembly and then the heater/a/c box it is in the hvac module.

SOURCE: bad heater core

look undre the passenger side dash and you will see a black box. Look closely and you will see screws in it around the edges. remove all the screws then remove the cover,there is the heater core, held in by 1 screw that is kinda hard to see. next look under the hood on the passenger side firewall right in front of the dash, you will see 2 hoses with clamps on them. loosen the clamps and remove the hoses. you may want to drain the radiator first but I never do

SOURCE: replace heater core in 2006 chevrolet HHR

Just like all other vehicles open hood and remove the bolts on the fire wall around the fan the fan will be bolted to the metal plate that is hiding the heater core.Know im not talking about the fan removel im talking about the plate the fan is bolted to.