Unfortunately on these series of engines, you really can not. Ford made the oil galleys very small to help maintain higher oil pressures, but this has ended up being a bad decision. You can not use a higher viscosity oil to help cushion worn metal to metal parts as it will not flow through the engine. You must use the thinner oil and live with a noisy engine or risk catastrophic engine failure.
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Unfortunately on these series of engines, you really can not. Ford made the oil galleys very small to help maintain higher oil pressures, but this has ended up being a bad decision. You can not use a higher viscosity oil to help cushion worn metal to metal parts as it will not flow through the engine. You must use the thinner oil and live with a noisy engine or risk catastrophic engine failure.