Replacing a rear hub seal is a job best left to a professional mechanic, as it involves dismantling and reassembling the rear axle. The mechanic will first need to drain the lubricating oil from the axle housing before removing the rear wheels and brake components. Once the axle is exposed, the mechanic can then remove the old rear hub seal and replace it with a new one. After reassembling the axle, the mechanic will refill the axle housing with fresh lubricating oil and check for any leaks.