So there's always lots of talk about RMS leaks on the 3.0 but is it possible to have the retainer plate in which the seal resides leak? I mean it's aluminum, no? And that's gotta expand at a different rate than the block....after years and years you'd think that could precipitate a leak?

I just did a rear main on a 3.0 ...confident everything was done right, but didn't seem to change the leak one bit. Used the sleeve from LCE, seal sold by LCE, seal was greased and seated dead square/flush, but no joy.

So now I've got the oil pan off, but I just really don't think the leak was oil pan. However it occurred to me as I stared at the bottom of the seal retainer this could cause a leak resembling RMS, and if I'm gonna tackle that I'd rather do it while the pan is still down....not that I want to pull the trans again - ugh!

Back of heads were bone dry when I just had the trans out for rear main

 

If I remember correctly when rebuilding my 3.0, The rear main seal aluminum plate you are talking about does have RTV on it to help seal.

There is a little channel you need to clean out then you put a new bead of RTV and reassemble. I believe I had to pull out two studs that went through the oil pan in order to make that aluminum RMS come off a lot easier. I just replaced the studs with 10mm bolts to make it easier in the future

I couldn’t find any pictures from my rebuild that show that bracket but I hope that info helps!

 

Ok, got it apart today. There was a paper gasket that had basically disappeared from 9 o'clock to 3 o'clock. It was not on the block or the the rear of the plate once disassembled.

Before removing the plate we did notice -- if we looked CLOSELY -- little chunks of gasket material hiding behind the plate near the bottom


Note tiny bit of leftover gasket at upper right hole

 

Glad you were able to find the issue! Just curious, what gasket did you end up replacing the retainer with? Paper, or RTV?

Man, seeing that pilot bearing reminds me of when mine seized up. Ended up having to use a slice of bread and a wooden dowel rod to get it out, because the grease trick wouldn’t work!

 

When I got in there the first time the pilot bearing was in a sad state. Even after the inner race came out the proper size collet on a blind hole puller was able to remove the small outer sleeve that was left behind. Bread and grease are another great trick to have in the arsenal but I love my blind hole pullers. Every situation is a little different

 

So D60, you bought a sleeve that fits over crank (like a seal ring on truck / bus axles that you 'press' onto the hub)?

Didn't know such were available. I try setting that seal just a mm or so from original position (must be careful, don't want it rubbing flywheel) so the new seal lip doesn't run in the groove from the old one.

 

Yep LCE sells the sleeve. I'd recommend the corresponding install driver, don't want to dent or wrinkle the sleeve. That said I'm sure hundreds of people have used a block of wood successfully.

The problem with setting the seal proud of the plate is that you really do want it as square as possible, or your seal becomes an oval (or ellipse?) around the crank. If you could machine a spacer to rest on the retainer plate that would be best. Some will say they've got a great eyeball but if you tap any single part too deep you can't easily pull it back out, so you're left chasing the deepest-set part of the seal.

Also I had the opportunity to see where the seal rides in the factory position by observing the shiny (ooh shiny!!) wear area on this sleeve. It's quite close to the block so IF one is going to try to just let the seal ride in a different spot, I concur with your instinct of pulling it BACK from the motor. I wouldn't go much deeper than stock or you risk slipping off the crank surface entirely.