Donaldson P550505 vs Baldwin B31: Oil Filter Compatibility
Compare Donaldson P550505 and Baldwin B31 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
Candidate adds ADBV
- 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 P550505 and Baldwin B31 specifications
How matching is scored| Specification | Donaldson P550505 | Baldwin B31 |
|---|---|---|
| Thread size | 13/16-16 | 13/16-16 |
| Gasket OD | 70 mm | 69.9 mm |
| Gasket ID | 60 mm | 60.9 mm |
| Can OD | 75 mm | 76.2 mm |
| Height | 113 mm | 88.9 mm |
| Internal bypass valve | No | No |
| Bypass PSID | Not applicable | Not applicable |
| Anti-drainback valve | No | Yes |
What matters in this specific comparison
Thread size matches: both are 13/16-16.
Gasket OD differs by 0.1 mm (Donaldson P550505: 70 mm, Baldwin B31: 69.9 mm).
Gasket ID differs by 0.9 mm (Donaldson P550505: 60 mm, Baldwin B31: 60.9 mm).
Donaldson P550505 is 24.1 mm taller (Donaldson P550505: 113 mm, Baldwin B31: 88.9 mm) -- check clearance before substituting.
Can OD differs by 1.2 mm (Donaldson P550505: 75 mm, Baldwin B31: 76.2 mm).
Anti-drainback valve differs: Baldwin B31 has one, Donaldson P550505 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.