WIX 51085 vs Donaldson P551042: Oil Filter Compatibility
Compare WIX 51085 and Donaldson P551042 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
Large bypass PSI mismatch: 14.5 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.
WIX 51085 and Donaldson P551042 specifications
How matching is scored| Specification | WIX 51085 | Donaldson P551042 |
|---|---|---|
| Thread size | 3/4-16 | 3/4-16 |
| Gasket OD | 71.98 mm | 72 mm |
| Gasket ID | 62.53 mm | 62 mm |
| Can OD | 93 mm | 93 mm |
| Height | 97.43 mm | 93 mm |
| Internal bypass valve | Yes | Yes |
| Bypass PSID | 8 - 11 | 20 - 28 |
| Anti-drainback valve | Yes | Yes |
What matters in this specific comparison
Thread size matches: both are 3/4-16.
Gasket OD is identical at 71.98 mm.
Gasket ID differs by 0.5 mm (WIX 51085: 62.53 mm, Donaldson P551042: 62 mm).
WIX 51085 is 4.4 mm taller (WIX 51085: 97.43 mm, Donaldson P551042: 93 mm) -- check clearance before substituting.
Can OD is identical at 93 mm.
Both open their bypass valve in a comparable range: WIX 51085 at 8-11 psi, Donaldson P551042 at 20-28 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.