[HWYSTR455]

Originally Posted by AdamIsAdam

Oh, and before I had an STP filter, now a K&N.

Filter media in a K&N is finer, and that could have alone caused the drop in psi. Try a PF24 AC as a baseline for pressure.

Where do you take the psi reading from, filter housing or rear of block? Rear of block is usually 5-10 or so psi less than at the filter housing.

Bearing clearances pretty much dictate what your psi will be, as well as the oil weight.

Thinner oil does find a way to leak easier than thicker, and syn adds to that. Sometimes additives in syn can impact (shrink or swell) rubber gaskets, which is what the balancer and oil pan front & rear are. Same with rear main seals. It should settle after a few heat cycles, if not, you may need to change them.

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