how do i fix or maintain a pinion seal leak?

Hello, An pinion seal is fairly complicated to repair, since the prelaod must be set in order to ensure the life of the pinion shaft bearing in the differential case. If you have the proper tooling and experience, you can complete this in a day, but if the driveshaft and yoke are not installed in the correct orientation, or the preload is set too loose or tight, you will have driveline vibration and pinion bearing failure very soon. I'd really recommend to use a certified professional to complete this repair if you are not well versed.