Baldwin B9 vs WIX 51620: Oil Filter Compatibility

Compare Baldwin B9 and WIX 51620 oil filters by compatibility, dimensions, thread size, gasket fit, bypass valve, anti-drainback valve status, and match confidence. Use this comparison as a fitment review, not as an automatic substitution guarantee. Both use a 13/16-16 thread.

Quick verdict

RISKY

Both use a 13/16-16 thread.

  • Thread size is the first hard-fit check for any comparison of spin-on filters.
  • Gasket OD and gasket ID are the most important seal-related dimensions.
  • Height differences can matter for clearance even when thread and gasket fit appear close.
  • Bypass and anti-drainback differences may be important, depending on the application.

Baldwin B9 and WIX 51620 specifications

How matching is scored
Specification
Baldwin B9
WIX 51620
Thread size13/16-1613/16-16
Gasket OD91 mm87.48 mm
Gasket ID80 mm78.74 mm
Can OD93.7 mm93.75 mm
Height136.5 mm132 mm
Internal bypass valveNoYes
Bypass PSIDNot applicable8 - 11
Anti-drainback valveYesYes

What matters in this specific comparison

Thread size matches: both are 13/16-16.

Gasket OD differs by 3.5 mm (Baldwin B9: 91 mm, WIX 51620: 87.48 mm).

Gasket ID differs by 1.3 mm (Baldwin B9: 80 mm, WIX 51620: 78.74 mm).

Baldwin B9 is 4.5 mm taller (Baldwin B9: 136.5 mm, WIX 51620: 132 mm) -- check clearance before substituting.

Can OD is identical at 93.7 mm.

Bypass valve presence differs: WIX 51620 has one, Baldwin B9 does not.

Open related filters

Before substituting, verify thread fit, gasket sealing dimensions, height clearance, bypass behavior, and anti-drainback requirements for your specific application.