Unless you like taking the transmission out. I got the honor of doing that twice yesterday. My Z had a slight leak when I bought it so when I changed to a manual trans I of course installed a new rear main seal. I used a Felpro seal since that is what's in the VG in my Pathfinder and it works fine.

After the swap and new seal still leaked slightly leaving a small oil spot after setting overnight. It's been doing this for six months but it wasn't a major problem so I didn't worry about it. I recently decided to install a lightened flywheel so I installed it yesterday morning along with a new Felpro seal. I got it back together and took it for a drive and stopped to check it about 20 miles later. Oil was running out of the bellhousing in a steady drip.

A couple of calls later I found an OEM seal at a Nissan dealer so I was off to get it. Spent the afternoon pulling the trans again and got it done last night and drove it more today and for the first time the Z is leak free.

What I found out about the seals is that they all position the lip in a different area. The crank has a groove where the original seal ran and the Felpro seals were positioning the lip right next to but not exactly in the groove. The new OEM Nissan seal is not as thick and positions the seal much farther in than either the original or Felpro seal. I even dug up on old seal out of the Pathfinder and it was positioned different yet. I figure the Felpro seal was walking in and out of the groove basically pumping oil out of the engine because neither of the Felpro seals were damaged.

Just a heads up that might help someone. I figure if your crank is grooved make sure the new seal sets exactly in the groove or way away from it.

 

Good info...

Just a heads up to you, there's a reason most Z people will tell you to always use Nissan gaskets and seals...

 

I usually do but just had one of Felpro seals on the shelf that I was going to use in a VG30E.

I am pleased to report that 770 miles later the Z is still leak free.