my expedition has 115k on it now and im gonna change the plugs. my question is should i put any insert in there or is there anything to prevent it from blowing out or just put the plugs in and torque them and hope for the best?

 

I used factory Motorcraft plugs and tightened them to about 30 ft lbs of torque. No anti seize. You don't need an insert until one of them blows out. Factory manual states 12-14 lbs I think but other sources say to tighten them 28-32 lbs to prevent them from working their way loose and blowing out. Motorcraft plugs are nickel plated so they *shouldn't* need any anti seize. The front 4 are easy- the rest can be a pain. I remember I pulled the fuel rail on the driver side so I put some new o rings on the injectors. Here's some info from one of the places that fixes the blown out plugs.
http://blownoutsparkplug.com/faqs.htm