When I bought Pennzoil motor oil, I was given a free name brand oil filter. I used machinist tools to measure and compare it with a Toyota filter. The non Toyota filter height was different than a Toyota filter by 0.015 inches on one side, which means the filter wasn't square and would not seal properly, allowing some oil to bypass the filter.

Next time you change the oil, measure the Jiffy Lube oil filter height at four locations, 90, 180, 270 and 360 degrees using a machinist caliper. Also inspect the paper filtering material. It's folded, rolled and joined. Inspect the seam. It may be gapped open, allowing oil to bypass the filter. I've cut open white box Jiffy Lube filters and once found a one-third section of the filter paper missing.