Heater no longer blows hot

If you are losing coolant and once it gets low enough then the heater core will lose coolant as well and could lose heat. I would suggest to keep the coolant topped off to start but we need to confirm why you are losing coolant.

https://www.2carpros.com/articles/head-gasket-blown-test

I would suggest to test the head gasket and make sure that is the issue and then we will need to repair that, fill the coolant and retest the heat.

Let me know what you find with the head gaskets and we can go from there.

Would blown head gasket cause loss of coolant? Started truck white smoke started then loss coolant in radiator.

Sure would. The white smoke is the coolant that is getting burned and turned to steam in the engine and put out the exhaust. Here is a guide that explains this in more detail:

https://www.2carpros.com/articles/white-smoke-or-steam-coming-from-the-exhaust-pipe

Got p0301 code. What else would this indicate beside the head gasket? Thanks for all your help.

Hello,

Your code is a misfire code and can very well be related to the head gasket failure making one of your plugs fowl out making the car run rough to.
Thanks for using 2CarPros.
Tom

Thanks for the help. Expecting the worse so anything else is a win. Thanks again for your help.

Yeah. Unfortunately a misfire code with the other things would just point to an issue with the head gasket relating to cylinder 1.

A compression test could help prove this out as well.

https://www.2carpros.com/articles/how-to-test-engine-compression

Unfortunately the more that we get into this, I feel pretty confident that this is a head gasket issue.

Unfortunately the head gasket was the problem. Hoping there are no other problems. If anything else comes up I definitely will address them with you. Thanks again for all your help.

Glad you figured it out. Thanks for the update. Thanks for the willingness to come back. Please tell your friends and talk to you next time. Thanks

Definitely will. Thanks again your expertise and help.