I Found this out the hard way after wrestling with Camoit's old motor for a few hours. 2wd oil pan does interchange, but there is a problem.

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ID:	1391This is a 2wd oil pan, this rear slope of the sump is too shallow hits the x-member and does not allow motor to come to full rest on motor mounts. There for a 4wd oil pan must be used. Thankfully my old oil pan bolted right up along with pick-up tube.