2026-08-01
Oil seals prevent lubricant from leaking and keep dirt out of rotating shafts. In tractors, combines and tillage equipment, a failed seal can lead to bearing damage, contamination and costly downtime.
Every oil seal is defined by ID x OD x T (thickness). For example TC 50x72x10 means 50mm shaft diameter, 72mm housing bore and 10mm thickness. Always measure with calipers before ordering.
TC (double-lip with spring): Most common for rotating shafts. The spring-loaded lip keeps constant contact.
SC (single-lip): Simpler, lighter duty, for splash lubrication.
TB (rubber-covered OD): Better sealing in rough housing bores.
NBR (Nitrile): Standard for most agricultural applications. -40 to +120C, resists mineral oils. Most cost-effective.
FKM (Viton): High-temperature (+200C) or aggressive fluids. Costs more, lasts longer in severe conditions.
Hardening/cracking = over-temperature. Worn lip edge = abrasive contamination. Spring pop-out = installation damage or shaft run-out.
Quick sizing chart:
| Application | Common Size (mm) | Type |
|---|---|---|
| Crankshaft front | 40x62x10 | TC NBR |
| Crankshaft rear | 100x125x12 | TC NBR |
| Gearbox input | 35x52x8 | TC NBR |
| Hub/wheel | 72x95x10 | TC FKM |
Bottom line: with ID x OD x T and the application, you have everything needed. Send us your measurements or OEM part number.