If you clean the engine down, you will be able to see which area is causing the most leakage. Check the rear main crankshaft bearing as a first priority. If you find oil leaking there a common problem there is the drain back hole in the rear bottom bearing cap has become clogged with oil residue and carbon residue, and will not allow the oil to drain back into the sump. As stated there is no rear main crankshaft seal, so if the LD rain back hole is blocked ,oil runs straight out the back of the engine. There is a floating ball in the drain back hole of the rear lower bearing that prevents oil draining out of the engine back bearing when driving up hills. The ball must be free and clean to float backwards and forwards to accommodate oil draining back to the pan , and prevent oil lose going up hills.
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