Anyone ever change their threaded freeze/core plugs?

(98 TJ 4.0 w/ax15) 98k miles

About to change my freeze/core plugs as part of an overhaul. Had a leaking rear one.

My question, has anyone changed those little threaded core plugs before? Along with their freeze plugs? Should they be replaced along with all freeze plugs? I’m thinking not necessary but I should mention my cooling system was very neglected by PO, I’ve since changed everything minus the heater core.

Also Jeep has been In Texas it’s whole life so never had salty roads to worry about. Just some previous idiots neglect.

Thanks y’all!

(Also I assume the rear one has oil behind it? So mostly talking about the ones on side of the block however I am also gonna do my RMS so while engine has no oil may change cam plug)

P man said:

If I am there and access is easy I'm replacing every plug I can taking care to use proper thread sealant where applicable

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Thanks for the reply! I’ll go ahead and change em while I’m in here and use Teflon tape or what ever is best after a little research. Thanks P man!

TJ4Jim said:

That's a solid steel plug and it's not going anywhere and it's accessible.

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Thanks Tj4Jim! Looks like I’ll be replacing them while I’m in here.

TJ Jim said:

Is there a plug at the back of the block against the firewall side?

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Yes there’s a plug on the back of the head against the firewall. That’s actually the one I had a leak from, one of the bigger ones not the small threaded ones. I have the tranny and t case out and have loosened the motor mounts and tilted the engine to get to it. Looks like I’ll have just enough room

TJ Jim said:

Is there a plug at the back of the block against the firewall side?

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My leaking one is directly above these. Gonna change em all