Cost to rebuild or replace your transmission. A minor leak can turn into a major problem if left alone. A low transmission fluid level or various component failures of the transmission can severely damage a transmission, leading to the need Transmission Repair Services One of the most common maintenance issues is low fluid level caused by a transmission leak. Because transmissions are sealed, a leak indicates a problem. Common causes of leaks include a breach in the pan gasket, an axle seal leak and fluid seepage.