Bosch 3423 vs FRAM HP4: Oil Filter Compatibility
Compare Bosch 3423 and FRAM HP4 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
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.
Bosch 3423 and FRAM HP4 specifications
How matching is scored| Specification | Bosch 3423 | FRAM HP4 |
|---|---|---|
| Thread size | 13/16-16 | 13/16-16 |
| Gasket OD | 70 mm | 71 mm |
| Gasket ID | 62 mm | 62 mm |
| Can OD | 75.01 mm | 95 mm |
| Height | 103.99 mm | 111 mm |
| Internal bypass valve | No | Yes |
| Bypass PSID | Not applicable | 22 |
| Anti-drainback valve | Yes | Yes |
What matters in this specific comparison
Thread size matches: both are 13/16-16.
Gasket OD differs by 1 mm (Bosch 3423: 70 mm, FRAM HP4: 71 mm).
Gasket ID is identical at 62 mm.
FRAM HP4 is 7 mm taller (Bosch 3423: 103.99 mm, FRAM HP4: 111 mm) -- check clearance before substituting.
Can OD differs by 20 mm (Bosch 3423: 75.01 mm, FRAM HP4: 95 mm).
Bypass valve presence differs: FRAM HP4 has one, Bosch 3423 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.