Here is the best available, part‑specific info for those filters; in all cases you should still confirm on the box/can at purchase because country of origin can vary by batch.

Wix 51515 and 51515XP

Wix 51515 A current catalog listing shows “Country of Origin Primary): US” for the 51515. Another supplier specifically lists “Origin Country: US” for this part. There are also older listings that show some 51515 stock as “Country of Origin: China,” so there may be mixed or legacy inventory.  ^{20 21 22}
Wix 51515XP A recent catalog entry for 51515XP lists “Country of Origin Primary): US.” However, users have reported some Wix XP part numbers coming from Mexico, so checking the box is still important.  ^{23 24}

Fram PH8A

A Canadian distributor lists PH8A as “Made in USA,” with matching dimensions for the standard spin‑on filter.  ²⁵
Framʼs own plant footprint is heavily US‑based, but they do not guarantee every part number is always US‑made; you still need to verify the “Made in …” marking on a given PH8A.  ²⁶

ACDelco PFL400A

Multiple current parts catalogs describe specifications and features for PFL400A but do not explicitly list the country of origin in the public spec block.  ^{27 28}
ACDelco often sources Gold Professional) filters from US plants but also uses non‑US plants; without an explicit COO line for PFL400A, you must rely on the box/can label for this one.  29

Motorcraft FL‑1A

FL‑1A is still a current Motorcraft filter with multiple modern variants; recent discussions and reviews focus on design and media differences but do not clearly state a single, consistent country of origin.  ^{30 31}
Historically many FL‑1A filters were made in USA by Purolator, but there are also examples from other countries; again, the physical filter/box is the only reliable way to confirm COO for your specific FL‑1A.  ^{32 33}