Head gasket question?

[Turbo6Tech84]

Just pondering this around would like some a more educated opinions on this. Just replaced my heater core about a month or two. Noticed the overflow bottle is low every so often so I refill it. Was wondering if my head gaskets might have a slow leak in them, never touched them before. I'm thinking it could be just the heater core filling up and the air is getting out of the system. I might just be crazy but what are some checks I can do to just be certain. Also my trans is slipping 2nd gear right now and I get some low knock numbers on that shift, I should really just turn the boost way down. Im currently only running 13 at best psi to be on the safe side. The highest knock reading I got was 3.2 something around there. Just wanna make sure im not damaging anything when I go cruising. Planning on getting the trans fixed soon just gotta get my funds up. Any info will be appreciated. I just cant wait to get all the demons out of this car and start enjoying alittle more.

 

[turbojd]

Check and make sure that the heater water valve isn't leaking, mine was and I had to replace it, just another thing to check.

 

[Turbo6Tech84]

I'll check that out this weekend then thanks

 

[87granny]

Also check the freeze plugs espessially the ones on the back of the engine have to remove insp. cover ask me how long it took to find that one