2001 Dodge Intrepid SE Leak from rear of engine collar behind oil pan?
It's hard to say without a picture of what you refer to as a 'collar', the rear main seal is in that area, but that would leak oil. You might also be referring to a freeze plug, which would leak coolant (or water if that's all you have in your radiator). If a freeze plug blew out you would have a major water/coolant leak. Otherwise you have a gasket issue.
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