Donaldson P550162 vs Baldwin B1421: Oil Filter Compatibility

Compare Donaldson P550162 and Baldwin B1421 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.

Quick verdict

SAFEScore: 93

These filters may still be worth comparing, but thread fit, gasket sealing dimensions, height clearance, bypass behavior, and anti-drainback requirements should be reviewed before substitution.

  • 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.

Donaldson P550162 and Baldwin B1421 specifications

Specification
Donaldson P550162
Baldwin B1421
Thread sizeM20x1.5M20x1.5
Gasket OD64 mm64 mm
Gasket ID54 mm54.1 mm
Can OD81 mm77 mm
Height86 mm87.3 mm
Internal bypass valveYesYes
Bypass PSID11 - 1514
Anti-drainback valveYesYes

What matters most in this comparison?

Thread match: A direct spin-on substitute starts with the same thread size. If the threads differ, the comparison stops there.

Gasket fit: Even when thread size matches, the gasket outside diameter and inside diameter still control whether the filter seals safely against the mounting surface.

Height difference: Small height differences may be acceptable, but longer filters can create clearance problems in tighter installations.

Valve behavior: Bypass and anti-drainback differences can matter in real-world service, especially on cold start or in applications sensitive to oil drain-back.

Related filter pages

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