Fleetguard LF3421 vs Fleetguard LF3861: Oil Filter Compatibility

Compare Fleetguard LF3421 and Fleetguard LF3861 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

RISKY

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 LF3421 and Fleetguard LF3861 specifications

How matching is scored
Specification
Fleetguard LF3421
Fleetguard LF3861
Thread size1-12 UNF-2B1-12 UNF-2B
Gasket OD71.98 mm71.98 mm
Gasket ID62.53 mm62.53 mm
Can OD94 mm94 mm
Height206 mm175 mm
Internal bypass valveUnknownUnknown
Bypass PSIDUnknown20.16
Anti-drainback valveUnknownUnknown

What matters in this specific comparison

Thread size matches: both are 1-12.

Gasket OD is identical at 71.98 mm.

Gasket ID is identical at 62.53 mm.

Fleetguard LF3421 is 31 mm taller (Fleetguard LF3421: 206 mm, Fleetguard LF3861: 175 mm) -- check clearance before substituting.

Can OD is identical at 94 mm.

Open related filters

Before substituting, verify thread fit, gasket sealing dimensions, height clearance, bypass behavior, and anti-drainback requirements for your specific application.