Well this is kind of weird but I had my drain plug basically fuse itself to my oil pan. I have been changing oil since I was 14 and this is the first time I have ever not been able to get the plug out. I have had a hard time before actually my 05 dodge magnum with same hemi I ended up having to replace it but never stuck so bad.
I took it into the mechanic figuring they could work some magic but no. They had some better tools to grab onto the head but it was not moving and something was going to break being probably the metal bung that is pressed into the cast plasticish oil pan then I would be out a car and $1500 by their account because they would have to drop the front diff to get to the oil pan and the pan itself isn't exactly cheap.
Anyways I told them to stop trying to get the plug out and I would figure something else out. I figured the plug could be drilled out enough to relieve whatever pressure was keeping it in there so tight so that was my plan. I got a new drain plug a better one that has a 5/8 head and also another rubber gasket actually in the threads of the bolt to help leaks, not that I have ever had a problem but why not splurge the 10 dollars.
So I planned to start with a small drill bit and work my way up continuing to drill the bolt hopefully relieving the tension so I could back it out without having to retap anything. I wouldn't try this if you don't feel comfortable with precision drilling just as a disclaimer. Its not a super easy angle to match. I had my shop vac sucking up as much metal shavings as i could between drill bits. Oh there is going to be a lot of oil to deal with after you get all the way through. I tried to drill without going all the way through till about a 1/4" bit then decided once I got any bigger than that it was going to be to hard literally to drill the bigger bits through. Long story long i had to drill almost the entire threads out before it let loose then I was lucky enough to be able to hand unthread it with no messed up internal threads.
Just as an fyi i also had a fire extinguisher next to me and a lot of rags to soak up the oil that just would not make its way out till I started drilling every time. Also I ran about 3 quarts of oil through just to flush any metal that might have made its way into the oil pan.
I'm not telling anyone to do this by the way, but it might be an option if your against the rock and hard place that I was. Also After I changed the oil and drove for a couple days i replaced the new oil filter again in case it was catching some shrapnel. Time will tell how it does. For now she's back to normal and the engine sounds good.