Fleetguard LF779 vs FRAM PH3980: Oil Filter Compatibility
Compare Fleetguard LF779 and FRAM PH3980 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 M18x1.5 thread.
Quick verdict
Both use a M18x1.5 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.
Fleetguard LF779 and FRAM PH3980 specifications
How matching is scored| Specification | Fleetguard LF779 | FRAM PH3980 |
|---|---|---|
| Thread size | M18x1.5 | M18X1,5 |
| Gasket OD | 71.88 mm | 71.1 mm |
| Gasket ID | 62.48 mm | 62.5 mm |
| Can OD | 76 mm | 75.79 mm |
| Height | 117 mm | 125.43 mm |
| Internal bypass valve | No | No |
| Bypass PSID | Not applicable | Not applicable |
| Anti-drainback valve | No | Yes |
What matters in this specific comparison
Thread size matches: both are M18x1.5.
Gasket OD differs by 0.8 mm (Fleetguard LF779: 71.88 mm, FRAM PH3980: 71.1 mm).
Gasket ID is identical at 62.48 mm.
FRAM PH3980 is 8.4 mm taller (Fleetguard LF779: 117 mm, FRAM PH3980: 125.43 mm) -- check clearance before substituting.
Can OD differs by 0.2 mm (Fleetguard LF779: 76 mm, FRAM PH3980: 75.79 mm).
Anti-drainback valve differs: FRAM PH3980 has one, Fleetguard LF779 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.