On the front tires, it doesn't look like you can reach the inside valve stem without removing the tire.
The tire is holding at 40 PSI, I will check it every couple of days, it took a long time to get down to where it was too low to yard drive. I may try changing the schrader valve core and see what happens, it was really hard to tell where the final leak was since the tire is still on the truck. Once I get it off, I will be able to figure it out and fix it.
Is the turret valve, the part that cones out of the rim?