FKM Oil Seals Rotary Shaft Seal TC Double Lip w Spring Dust Grease 62-70mm ID

Measure three dimensions directly from the old seal or the shaft/housing: inner diameter (ID) — the shaft diameter the lip contacts; outer diameter (OD) — the housing bore the steel case presses into; and width (thickness). Match all three to the variant selector above. If the old seal is damaged, measure the shaft OD for ID, the housing bore ID for OD, and the housing recess depth for width.

NBR seals are adequate for standard mineral oils at moderate temperatures (up to roughly 120 °C). FKM becomes the correct choice when operating temperatures exceed 120 °C continuously, when the fluid contains synthetic additives, ATF, or fuel vapors, or when the seal is exposed to ozone and UV degradation over long service intervals. FKM retains its elasticity and sealing force in conditions that cause NBR to harden and crack.

TC is an industry-standard profile code indicating a double-lip seal with a garter spring. The primary (inner) lip is spring-loaded to maintain radial contact with the rotating shaft. The secondary (outer) lip faces outward to exclude dust, dirt, and moisture. This two-barrier design makes TC seals the standard choice for axles, gearboxes, and any shaft that operates in a contaminated environment.

A proper seal driver or a flat-faced socket matching the OD of the seal is strongly recommended. Driving the seal in with a hammer directly risks cocking the steel case, deforming the lip, or scoring the housing bore. The seal must be pressed in squarely and flush (or to the specified depth) to achieve a leak-free press-fit. Clean the housing bore and apply a thin film of the system fluid to the outer case before installation.

Yes. FKM fluoroelastomer has broad compatibility with fully synthetic gear oils (PAO and ester-based), automatic transmission fluids, and power steering fluids. If you are unsure about a specific fluid formulation — particularly those containing aggressive friction modifiers — contact us to confirm compatibility before ordering.

For optimal seal life, the shaft surface in the contact zone should have a finish of Ra 0.2–0.8 µm (approximately 8–32 µin) with a lead-free ground or polished finish. Rough, pitted, or corroded shaft surfaces accelerate lip wear and cause premature leakage. If the shaft shows a wear groove from the old seal, reposition the new seal slightly axially to contact an unworn surface, or use a shaft repair sleeve.

The outer face of the seal should be flush with the housing face or recessed to the depth specified for your application. Run a finger around the full circumference of the installed seal — the case should feel uniformly seated with no rocking or tilt. Before filling with fluid, rotate the shaft by hand to confirm the lip tracks smoothly without binding or squealing.