Mazda AJ04-14-302A vs WIX 51521: Oil Filter Compatibility
Compare Mazda AJ04-14-302A and WIX 51521 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.
Mazda AJ04-14-302A and WIX 51521 specifications
How matching is scored| Specification | Mazda AJ04-14-302A | WIX 51521 |
|---|---|---|
| Thread size | 3/4-16 | 3/4-16 |
| Gasket OD | 72 mm | 71.98 mm |
| Gasket ID | 63 mm | 62.53 mm |
| Can OD | 93.19 mm | 92.99 mm |
| Height | 110.19 mm | 96.01 mm |
| Internal bypass valve | Yes | Yes |
| Bypass PSID | 8 - 11 | 8 - 11 |
| Anti-drainback valve | Yes | Yes |
What matters in this specific comparison
Thread size matches: both are 3/4-16.
Gasket OD is identical at 72 mm.
Gasket ID differs by 0.5 mm (Mazda AJ04-14-302A: 63 mm, WIX 51521: 62.53 mm).
Mazda AJ04-14-302A is 14.2 mm taller (Mazda AJ04-14-302A: 110.19 mm, WIX 51521: 96.01 mm) -- check clearance before substituting.
Can OD differs by 0.2 mm (Mazda AJ04-14-302A: 93.19 mm, WIX 51521: 92.99 mm).
Both open their bypass valve in a comparable range: Mazda AJ04-14-302A at 8-11 psi, WIX 51521 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.