Champ PH400 vs WIX 51521: Oil Filter Compatibility
Compare Champ PH400 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.
Champ PH400 and WIX 51521 specifications
How matching is scored| Specification | Champ PH400 | WIX 51521 |
|---|---|---|
| Thread size | 3/4-16 | 3/4-16 |
| Gasket OD | 70.1 mm | 71.98 mm |
| Gasket ID | 62.5 mm | 62.53 mm |
| Can OD | 93.73 mm | 92.99 mm |
| Height | 104.9 mm | 96.01 mm |
| Internal bypass valve | Yes | Yes |
| Bypass PSID | 14 | 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 1.9 mm (Champ PH400: 70.1 mm, WIX 51521: 71.98 mm).
Gasket ID is identical at 62.5 mm.
Champ PH400 is 8.9 mm taller (Champ PH400: 104.9 mm, WIX 51521: 96.01 mm) -- check clearance before substituting.
Can OD differs by 0.7 mm (Champ PH400: 93.73 mm, WIX 51521: 92.99 mm).
Both open their bypass valve in a comparable range: Champ PH400 at 14-14 psi, WIX 51521 at 8-11 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.