This CORTECO crankshaft seal, part number 12011394B, is specifically engineered for manual transmission applications. It plays a crucial role in preventing oil leaks from the crankshaft, maintaining proper lubrication within the transmission system. Crafted with durable materials, this seal is built to withstand the demanding conditions of engine operation. Its precise design ensures a tight fit, contributing to the longevity and reliable performance of your vehicle's manual gearbox. Proper sealing is essential for the health of your transmission. A failing seal can lead to oil loss, potentially causing damage to internal components and affecting shifting performance. Replacing a worn seal with a quality part like this CORTECO unit helps maintain optimal operating conditions.