Baldwin BT251 vs WIX 51431: Oil Filter Compatibility
Compare Baldwin BT251 and WIX 51431 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 3/4-16 thread.
Quick verdict
Both use a 3/4-16 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 BT251 and WIX 51431 specifications
How matching is scored| Specification | Baldwin BT251 | WIX 51431 |
|---|---|---|
| Thread size | 3/4-16 | 3/4-16 |
| Gasket OD | 71.4 mm | 71.35 mm |
| Gasket ID | 62.7 mm | 61.85 mm |
| Can OD | 93.7 mm | 107.7 mm |
| Height | 181 mm | 143.2 mm |
| Internal bypass valve | Yes | Yes |
| Bypass PSID | 8 | 8 - 11 |
| Anti-drainback valve | Yes | Yes |
What matters in this specific comparison
Thread size matches: both are 3/4-16.
Gasket OD differs by 0.1 mm (Baldwin BT251: 71.4 mm, WIX 51431: 71.35 mm).
Gasket ID differs by 0.9 mm (Baldwin BT251: 62.7 mm, WIX 51431: 61.85 mm).
Baldwin BT251 is 37.8 mm taller (Baldwin BT251: 181 mm, WIX 51431: 143.2 mm) -- check clearance before substituting.
Can OD differs by 14 mm (Baldwin BT251: 93.7 mm, WIX 51431: 107.7 mm).
Both open their bypass valve in a comparable range: Baldwin BT251 at 8-8 psi, WIX 51431 at 8-11 psi.
Open related filters
Before substituting, verify thread fit, gasket sealing dimensions, height clearance, bypass behavior, and anti-drainback requirements for your specific application.