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Are you having a problem with the heater for inside the cab you mean right?
Let the engine warm up, does the engine reach "warm" Also feel the heater hoses, are they hot or cold?
Yes inside the cab, I drove the truck for about 20 min. on the highway, still no heat.
Do the heater hoses (the 2 smaller rubber hoses that go into the firewall from under the hood, passenger side)
do they get hot?
Ok, neither get hot?
ARe the radiator hoses getting hot?
Sorry, I didn't see you replied earier.
If the heater hoses aren't hot it means coolant isn't flowing through the heater core.
This could be due to a clogged heater core or weak water pump.
You should let the vehicle cool down.
Remove the heater hoses and apply some high pressure air to the inlet side of the heater core.
Blow out the heater core to get anything that could be obstructing the flow.
Be careful you are going to lose coolant and possibly make a mess.