FRAM PH4558 vs Baldwin BT310: Oil Filter Compatibility
Compare FRAM PH4558 and Baldwin BT310 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 M20x1.5 thread.
Quick verdict
Large bypass PSI mismatch: 10 psi
- 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.
FRAM PH4558 and Baldwin BT310 specifications
How matching is scored| Specification | FRAM PH4558 | Baldwin BT310 |
|---|---|---|
| Thread size | M20x1.5 | M20x1.5 |
| Gasket OD | 71 mm | 69.9 mm |
| Gasket ID | 61 mm | 60.9 mm |
| Can OD | 76 mm | 76.2 mm |
| Height | 85 mm | 89.7 mm |
| Internal bypass valve | Yes | Yes |
| Bypass PSID | 12 | 2 |
| Anti-drainback valve | Yes | Yes |
What matters in this specific comparison
Thread size matches: both are M20x1.5.
Gasket OD differs by 1.1 mm (FRAM PH4558: 71 mm, Baldwin BT310: 69.9 mm).
Gasket ID differs by 0.1 mm (FRAM PH4558: 61 mm, Baldwin BT310: 60.9 mm).
Baldwin BT310 is 4.7 mm taller (FRAM PH4558: 85 mm, Baldwin BT310: 89.7 mm) -- check clearance before substituting.
Can OD differs by 0.2 mm (FRAM PH4558: 76 mm, Baldwin BT310: 76.2 mm).
Both open their bypass valve in a comparable range: FRAM PH4558 at 12-12 psi, Baldwin BT310 at 2-2 psi -- these ranges do not overlap.
Open related filters
Before substituting, verify thread fit, gasket sealing dimensions, height clearance, bypass behavior, and anti-drainback requirements for your specific application.