TC TG Oil Seal Skeleton FKM Rubber Framework Double Lip Sealing Ring 68-100mm

Remove the old seal and measure three dimensions with calipers: inner diameter (shaft diameter), outer diameter (housing bore), and depth (axial width). All three must match the replacement seal. If the old seal is too damaged to measure, consult your equipment service manual or look up the OEM part number to cross-reference dimensions.

Both TC and TG are double-lip seal configurations with a primary sealing lip and a secondary dust lip. The distinction relates to the lip geometry and garter spring arrangement used by different standards bodies. In practice, seals listed as TC/TG share the same outer envelope dimensions and are interchangeable in most applications when the bore and shaft diameters match.

FKM (fluoroelastomer, also sold under trade names such as Viton®) tolerates continuous temperatures up to approximately 200 °C (392 °F) and resists a broader range of synthetic lubricants, automatic transmission fluids, and mild chemical media. NBR (nitrile) is adequate for mineral oils at moderate temperatures but degrades faster in high-heat gearboxes, turbo-adjacent applications, or where synthetic fluids are used.

Clean the housing bore and shaft thoroughly. Lightly lubricate the sealing lip with the same fluid the seal will retain. Use a seal driver or a flat press plate sized to the outer diameter to press the seal in squarely — never hammer directly on the seal face. Press until the seal face is flush with or just below the housing bore face. Avoid dragging the lip over keyways or splines; use a thin sleeve or tape to protect the lip during installation.

The secondary dust lip provides a degree of water and moisture exclusion, making TC/TG seals suitable for equipment exposed to splash, rain, and dusty outdoor environments. However, these seals are not rated for continuous submersion or high-pressure water ingress. For applications with sustained water exposure, verify the specific FKM compound's water resistance rating.

For optimal lip seal performance, the shaft contact surface should have a finish of Ra 0.2–0.8 µm (approximately 8–32 µin) with a lead-free ground finish. Rough or scored shafts accelerate lip wear and cause early leakage. If the shaft shows grooves from the old seal, use a speedi-sleeve repair sleeve or replace the shaft section before fitting the new seal.

FKM rubber has good compatibility with most ATF formulations and conventional gear oils (GL-4, GL-5). For specific synthetic gear oils or specialty fluids, verify compatibility with the fluid manufacturer's seal compatibility data, as additive packages vary between brands and can affect elastomer swell rates over time.