How do you replace a heater core in a 1994 to 2001 dodge ram 1500?

Answer 1

The Heater core is difficult to replace on the RAM since it is buried in the plenum box. The box has a convenient door panel that you can open to remove and replace the core. The catch is that the convenient door is on the back of the box and you have to remove the heater box to get to it. This involves removing the steering wheel, steering column, complete dash panel, evacuating the AC, draining the radiator, and finally removing the heater box. Once you have the box out(8-12hrs), the core is simple to replace.

You want to be sure that the core is the problem before you undertake this process. If there is a strong smell of antifreeze in the cab or a puddle of coolant on the passenger side floor, the diagnosis is easy.

Check that the radiator is full, not the overflow tank, the radiator. On a cold engine you can remove the radiator cap and check the level. It should be full. If there is air in the system it will affect cab heating and engine cooling.

Another good check is to feel the two heater hoses going into the firewall from a cold start. The hoses should warm up at about the same rate and get uncomfortably hot-close to radiator temperature.

If the core appears to be OK, the next concern is with the blend doors that divert air through the heater core. This is a common failure on the RAM. Check heatertreater.net for an explanation of the operation of the system and a fix for the common problems. The RAM has four different DC servo motor controlled air flow doors that are susceptible to failure and all of these need to be checked by either observing the symptoms of failure or reading the codes. The problems are easy to fix with the HeaterTreater kits, but the OEM dealer fix requires removing the plenum box as described above. It is a costly repair if you take it back to the dealer and are not under warranty.

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look not to sound like a jerk or anything but ya'll are way over working yourselves. i just finished a heater core on a 1999 ram today and it took me 3 hours to complete the job. heres a step by step guide to make your life so much easier when replacing the heater core. the very first thing i would do is throw the haynes manual in the garbage for it gives the same instructions that ya'll are doin.

first disconnect the battery.

remove the 5 bolts at the top of dash nest to the winshield.

remove both passenger and driver kick panels. loosen both nuts on each side of the dash at the kick panels.

next you have 2 nuts in the very center of the dash at the transmission hump.remove both.

take panel off that covers the sterring column. remove the 2 nuts that hold the column up. let the column sag.thers a plate below the colun that's connected to the dash that needs to be removed. has 6 Phillips screws .that needs to be removed.

remove the 2 screws that hold the hood latch cable to the bottom of the dash.

remove the headlight wires to the back of the headlight switch.

remove the screws that go to the ac and heater controls. no need to disconnect the wires. position the ac and heater controls and push the assembly through the hole that it mounts in so you wont have to disconnect the wiring and vacum lines on it.

disconnect the wires to the back of the radio.

this should allow the dash to come out enough to almost lay on the seats.

now you can see the top of the heater core with the 2 tubes going through the fire wall. you will see 2 butterfly brackets on the cores tubes holding it in place.the first one has a ground strap that will be bolted to it. the second id up against the firewall and requires a short stubby screwdriver to get the screw out.

now go to the engine compartment and remove the heater hoses that connect to the heater core. there is no need to evacuate the ac. none of the ac interferes with removing the heater core. why everyone thinks it does beats me.

now you are ready to remove the heater core.

from the inside of the truck you don't have to take the ac/ heater box apart. the heater core will just lift out of the box.jus be advised when you are installing the new one be careful not to crack it or break the welds. both the pipes on the heater core will rotate 360 degrees so you can makeshift it back down in the hole while putting the pipes through the firewall at the same time. this being the hardest part of the job, but just be patient, it will go.

now put everything back together and you are done around 3 hours.

i don't know why everyone thinks you have to take out all the inst. cluster and evacuate the ac. that's way to much work that don't need to be done.

when you get everything back together and refill the radiator with coolant, start the vehicle up with the radiator cap off and turn the heat on. let the truck get warm and make sure the heat is blowing hot before you put the radiator cap back on. this will ensure that all the air pockets are out of the system.This is a excellent write up. I followed it today it works .One more step is to remove both A-piller covers,broke both of mine today but still money ahead.Thanks for the info.