Examine your new seal to get an idea of the structure of the old one. Either way the old and new seal both have a metal inner structure that you are drilling into, once you pass through that DON'T drill any deeper, we aren't trying to drill holes in the crank to lighten it. We just want to get under the outer layer of the rubber and through the metal lip in the seal. I think you could do 2 holes one at 3 and one at 9 without an issue. One at the 12:00, one at the 4:00, and one at the 8:00. You will also need to drill a couple small holes in the lip of the existing seal in order to screw your slide hammer into the seal (holes need to match the screw end of your slide hammer) . I got one for like 15$ at the local cheapo depot tool shop. Removal: You need a little screw in slide hammer. Not sure if auto parts store XY or Z sells one with the tool but it makes the install per the book if you will. That tool is a must have to properly complete this task. It comes with the new seal and the installation tool. The new seal kit from the dealer was 100$ (give or take a bit). However I had already purchased a Cummins OEM seal before the project started so it was going in lol. Well after further understanding the Cummins adapter plate and the seal, I don't really think I did. Now when I first started on my truck I 'thought' I had a rear seal leak. I had my transmission and flex plate out of the vehicle already, so it was a no brainer to replace this seal. I will start with the rear main seal because it was more straight forward. Keep em clean.įYI: My post is not a 100% how to, but a little reference and maybe some help to someone with similar issues.

I hate dirty engines and grease covered parts. Neither were bad enough to drip on the ground when parked overnight, but there was enough to make things turn oily on the surrounding areas. Before I started the work I knew I had an oil leak out of my front main seal on the crankshaft seal and I thought same for the rear. Recently I did some extensive engine work to my 20 with the 5.9L Cummins engine.

5.9 cummins rear main seal wear sleeve