Fleetguard LF3740 vs Fleetguard LF3420: Oil Filter Compatibility
Compare Fleetguard LF3740 and Fleetguard LF3420 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 1-12 thread.
Quick verdict
Both use a 1-12 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 LF3740 and Fleetguard LF3420 specifications
How matching is scored| Specification | Fleetguard LF3740 | Fleetguard LF3420 |
|---|---|---|
| Thread size | 1-12 UNF-2B | 1-12 UNF-2B |
| Gasket OD | 71 mm | 71.98 mm |
| Gasket ID | 62 mm | 62.54 mm |
| Can OD | 95 mm | 96 mm |
| Height | 222 mm | 205 mm |
| Internal bypass valve | Yes | Yes |
| Bypass PSID | 20.16 | 19 |
| Anti-drainback valve | Yes | Yes |
What matters in this specific comparison
Thread size matches: both are 1-12.
Gasket OD differs by 1 mm (Fleetguard LF3740: 71 mm, Fleetguard LF3420: 71.98 mm).
Gasket ID differs by 0.5 mm (Fleetguard LF3740: 62 mm, Fleetguard LF3420: 62.54 mm).
Fleetguard LF3740 is 17 mm taller (Fleetguard LF3740: 222 mm, Fleetguard LF3420: 205 mm) -- check clearance before substituting.
Can OD differs by 1 mm (Fleetguard LF3740: 95 mm, Fleetguard LF3420: 96 mm).
Both open their bypass valve in a comparable range: Fleetguard LF3740 at 20.16-20.16 psi, Fleetguard LF3420 at 19-19 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.