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2000 Silverado heater not working

My heater in my truck is not working. It’s a 2000 Silverado 5.3 Replaced the thermostat, flushed out the heater core, and checked to make sure the actuator under the passenger dash is moving when I switch from cold to hot. It just blows cold/ neutral air but never hot

Are both heater hoses from the heater core equally hot ? within a few degrees.

A plugged heater core can still flow quite a bit of water through it.

If possible, you might remove the actuator and see if you can manually move the blend door and then see if you have heat. There are 3 or 4 actuators under there (some easier to get to than others), so make sure you are looking at the correct one.

No one hose is hot and one is not even warm

sounds like a classic case of plugged heater core

My money is on a plugged heater core.

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I reverse flushed it, is there any other way to do it?