Does your differential leaks oil? Here’s how I replaced the pinion-oil seal at my 1956 Coupe DeVille.

This article is documented with some pictures in the gallery.

1. Remove driveshaft at differential. I wanted to overholt the drive, too. So I removed it also from the tranny. If you do that be aware that the tranny will lose oil if you wont’ insert a spare joke or drain tranny oil first.

2. Remove pinion joke at differential. It thought the lock nut would be very tight - but I was wrong; it was learly loose. Later I found out that the threads of the nut were worn and I need to replace with a new nut. The joke itself was removed easily. Perhaps you need a puller to remove the joke.

3. By removing the old oil seal it will be damaged - but since we want to replace this seal, dont’ care. Be very carefull to avoid damaging the oil seal seat at the differential housing! I guess you can use a screwdrive to remove the old seal - but I was affraid of damaging the seat, so I used a puller to remove the old seal. You can see pictures of my self made oil seal puller here.

4. Clean the oil seal seat at the differential housing and lubricate the seat with a thin film of sealing paste. Insert the new seal and press the seal into the seat very carefully to avoid tilt or distorsion of the new seat. There’s a special tool available to press the seal into the seat but if you don’t have it, you can also use a wooden block and a hammer to drive the seal in, like I did.

Replacement of the oil seal alone should not take more than 1 hour.