Any real mechanic worth a toot would know how to fix a stripped oil drain plug! Simply tap it out in a bigger size thread and install a bigger drain plug. Heli-coils are also an option if you can find one in the correct thread size.
Mine was stripped when I bought the Jeep. It already had an oversize plug in it that was stripped so my options were few.

To fix it, I tapped the pan out using a 1/2 tapered pipe thread tap and installed a 1/2 to 3/8 reducer/adaptor pipe bushing using red locktite permanently into the pan and then used a smaller 3/8 pipe plug in the adaptor for the removable drain plug. I now use the tapered 3/8 pipe plug only when draining the oil. No leaks at all and a permanent fix... All parts available at any local hardware store like ACE....

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Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited 
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
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Carter Intank-pmp
2mic.Sec.Fuel Filter
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